Doherty pounced in the 18th minute with Janmaat's 62nd minute own goal helping Wolves to a 2-0 victory over the basement side that moves them out of the relegation zone and up to 14th in the table.
Pedro Neto was a surprise replacement for the injured Diogo Jota but the forward repaid the faith shown in him by boss Nuno Espirito Santo with a memorable first Premier League start.
The 19-year-old Portuguese attacker gave a Watford defence still reeling from an 8-0 thrashing at the hands of Manchester City last weekend no time to lick their wounds with his electric pace.
With Adama Traore on the opposite right flank Wolves looked to bombard Watford with their pace on the wings as wide men Jonny and Matt Doherty pushed up in support.
That wide-play was the catalyst for the opening goal with Neto's turn of pace and tantalising ball across the face of goal leaving the ball on a plate for Doherty to fire home in the 18th minute.
From there, given Watford's last Premier League result, you'd have expected it to have been a mauling by Nuno's men.
But this side is still growing in confidence and did not make easy work of picking up their first three points of the season.
Rui Patricio had to work for his first league clean sheet since the opening day as the Portuguese shot-stopper made a fine double stop to thwart Jose Holebas and Tom Cleverley.
But Watford would shoot themselves in the foot from another right-wing attack.
Doherty's ball in was nodded on by Gibbs-White with Janmaat diverting the ball into his own net.
It was a mistake that would allow Wolves to cruise on and claim their first Premier League victory of the season.
It was far from perfect from Nuno's men with a number of loose passes and improvement needed in both attack and defence.
The answer is clearly in the wings but there is no doubt that Watford were the architects of their own downfall in this clash too with a number of wasted opportunities and Janmaat's own goal paving the way for Wolves to pick up their first three points of the season.
Nuno made one change from the side that drew 1-1 at Crystal Palace last Sunday.
The hero from Selhurst Park Diogo Jota was ruled out of contention for this clash due to a suspected foot injury.
That paved the way for Pedro Neto to get the nod on the left of the front three.
It would be the 19-year-old's first Premier League start for Wolves since joining from Italian side Lazio in the summer.
The youngster started Wolves' 4-2 penalty shoot-out victory over Championship side Reading in midweek and was one of two survivors from that game as Nuno made nine changes.
Neto and right wing-back Matt Doherty the only men to keep their spots in the starting XI as Nuno shifted from 3-5-2 to the 3-4-3 he deployed at Palace.
Romain Saiss was sent off for two yellow cards at Selhurst Park but after serving his one match ban in midweek he returned to join captain Conor Coady and Willy Boly in the back three.
Jonny Otto reclaimed the left wing role with Leander Dendoncker and Joao Moutinho starting in the centre of Nuno's midfield.
Adama Traore and Neto started either side of centre forward Jimenez in a front three as Wolves eyed their first three points of the season.
Watford's Wolverhampton born forward Andre Gray had to settle for a place on the bench as Quique Sanchez Flores handed a first league start of the season to ex-Arsenal man Danny Welbeck.
And it was Welbeck who was straight in the action as Wolves attacker Traore's loose pass fell into the wrong hands early doors.
Traore attempted to slide the ball inside from the right-wing but Watford's Abdoulaye Doucoure pounced in the Wolves half and released Welbeck who luckily tamely fizzed the ball past the left stick from distance.
But that did not deter Wolves who showed their teeth up the other end, though the loose passes did not stop there with Nuno's side losing possession a number of times.
Jimenez found space on the right of the box but his fierce angled effort rocketed into the side netting.
Wolves had struggled with their end product in recent games and it showed in some of their early attacks.
But the pace of their front three was evident as they looked to get in behind a Watford defence that had suffered an 8-0 defeat to Manchester City last weekend.
Traore released Doherty on the overlap on the right with the Watford defence left static.
Jimenez sprinted towards the near post with Neto steaming towards the penalty spot.
Doherty, in two minds, opted to fizz the ball in-between them both and the chance faded away.
Neto had started on the left but as Wolves countered he would use that electric pace as on the right too as Wolves targeted Jose Holebas.
After that wasted opportunity they got closer to goal minutes later as they used the pace of another forward in Neto to counter from a Watford corner.
Boly hooked the ball clear to Neto on the right wing and he accelerated at full speed towards goal.
The forward whipped in a tantalising cross from the right after drawing keeper Ben Foster and the Watford defence into his path but the ball missed the toe of Jimenez by a whisker at the back post.
It was a fine start by Neto who was at the forefront of Wolves' attacking play on the left-wing.
Using width was a tactic Wolves had deployed in the first half at Selhurst Park and started this clash with a similar plan.
And it was Neto who would finally find a way to unlock Watford's defence.
He breezed in to the box and sent the ball flying across the face of goal into the path of Doherty who tapped home in the 18th minute.
It was a deserved goal for Wolves and an improvement of the lack of ruthlessness in recent weeks.
At Selhurst Park they had 13 opportunities but could only convert one at the death.
Today they scored their second clear cut opportunity with Neto's pace leaving a Watford defence that had lost 8-0 to Manchester City in their last league game quaking in their boots.
But it was not just the Neto show at Molineux with Traore also making an impact on the right wing.
Like Neto, the front-man also has frightening levels of speed in his locker and he left Watford's defence petrified as he tore down the right flank and whipped in a cross that almost kissed the bar before curling away from the expectant Jimenez and Neto in the box.
Wolves had the more potent attacks in the first half but with only a goal to show for that control Watford still had a glimmer of hope.
Wolves sat back and invited pressure with the visitors enjoying 59 per cent of the possession at Molineux.
Wolves still looked to belacking in belief but faced a Watford side that refused to capitulate after that opening goal.
And with Welbeck in their side they always posed a threat up top as he found space in the box.
He tried to arrow the ball towards goal but his strike was blocked by the recovering Jonny.
It would be a slow and tepid end to the half with centre-half Saiss needing treatment on the pitch with Jimenez also receiving attention from the physio just before the break.
Both shook off the knocks to play on.
And it was the visitors who would make a change at the break but if was Watford that looked the brighter of the two sides in the second half.
Flores' basement side sensed a fight-back against a Wolves side that have also been lacking in confidence of late.
They pushed forward in search of a leveller but they could not find a way past Rui Patricio.
The Wolves shot-stopper acrobatically batted away Holebas' header and dusted himself down to thwart Tom Cleverley on the rebound at the near post.
That double Hornets chance woke Wolves up and they released Neto on that left flank once again.
The youngster rifled the ball straight down the throat of Foster and would make way for Gibbs-White moments later.
Wolves would kill off any hopes of a Watford come-back by netting their second after that substitution.
It was more of a case of Watford being the architects of their own downfall with footage that will not be happy viewing for Daryl Janmaat.
Doherty raced down that right flank again and whipped the ball into the mix.
Gibbs-White flicked the ball on but with no gold and black shirt nearby the chance looked to have have faded before Janmaat nodded past Foster in the 62nd minute.
It was a damning mistake from the Watford defender and one that could have left his team with no way back.
But Patricio had to work to keep the visitors out as Watford refused to go down without a fight.
Gray entered the fray but it was Welbeck who remained Watford's biggest asset.
The striker's curling effort was just tipped away but the Portuguese shot-stopper as the Hornets asked questions of Nuno's side.
Wolves should have put the game to bed seconds later after more delightful wing play.
Traore's curling ball from the right flew into the path of Jonny at the back stick but the diving wing-back could only divert the ball wide of the left stick.
Jimenez would make way for Cutrone as the half wore on but he would not get a chance to make it 3-0.
Doucoure fired straight down Patricio's throat in the closing stages but Wolves held on to keep that clean sheet and pick up all three points.
18 - GOOOOALLLLLLL! Wolves are ahead after such a silky passage of play! Moutinho's clever reverse pass finds Otto. He puts it down the line to Neto, who squares it across goal for Doherty to tap in. Liquid football.
54 - A shaky moment for Wolves. Watford substitute Pereyra confidently gets the better of Doherty and floats it to Holebas. His header is spilled by Patricio, who recovers to keep out Cleverley from close range.
61 - GOOOOAALLLLLLLLLL!! Nuno's charges double their advantage as Janmaat heads the ball into his own net! Doherty, after a one-two with Traore, plays a cross to Gibbs-White, who flicks it on before Janmaat inadvertently puts it past Foster.
Wolves (3-4-3): Patricio; Boly, Coady (c), Saiss; Doherty, Moutinho, Dendoncker, Otto; Traore (Neves, 87), Jimenez (Cutrone, 80), Neto (Gibbs-White, 57)
Subs not used: Ruddy (gk), Bennett, Kilman, Vinagre
Goals: Doherty (18), Janmaat OG (61)
Watford (4-2-3-1): Foster; Janmaat, Cathcart, Dawson, Holebas; Doucoure, Capoue (c); Sarr (Gray, 71), Cleverley, Deulofeu (Pereyra, 46); Welbeck
Subs not used: Gomes (gk), Kabasele, Femenia, Chalobah, Quina
Referee: Paul Tierney (Lancashire)