Villas-Boas went in to Sunday's game under pressure having failed to deliver a victory in his first three contests, but the 34-year-old left the Madejski with a broad smile after watching his team claim an easy 3-1 win.
The architect of the victory was Defoe. The 29-year-old got on the end of Aaron Lennon's cross to put Spurs ahead and added another in the second half after Gareth Bale had made it 2-0.
Defoe's future at White Hart Lane had been in doubt this summer after the club scoured the planet for a new striker, but the former West Ham man has now scored five goals for club and country so far this term.
"I'm extremely happy for him," Villas-Boas said.
"He is such a prolific striker for club and country. It's amazing how he sniffs out goal-scoring opportunities and makes the most of them.
"I know there were questions being raised about him being played up front on his own. On his own or with Emmanuel Adebayor alongside him, I think Jermain can continue to produce these kind of attacking opportunities.
"He has confidence as a striker and we are very grateful we can use this confidence at this moment."
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Spurs looked clueless at times in their 1-1 draw against Norwich last time out, but on Sunay they produced some of the football that set pulses racing during the reign of Villas-Boas' predecessor Harry Redknapp.
Aaron Lennon, Bale, Walker and Kyle Naughton all produced chaos down the flanks and Mousa Dembele put in an exceptional shift in the midfield to suggest that Spurs may not miss Luka Modric as much as they had thought.
Defoe's final goal, a slotted finish after a mazy run from the halfway line, has to be a contender for goal of the month.
Villas-Boas was delighted to see his team playing such enterprising football after the disappointment of the last three games in which Spurs looked timid at times.
"I'm extremely happy with the performance," he said.
"The players showed tremendous commitment, responsibility and concentration.
"They understood that we have been working so hard and they deserved to get this first win so the way they came into the game with that focus of wanting to put things in their place was very pleasing to see.
"They kicked out the anxiety and played in such a confident and concentrated way that they were able to express their talents and have fun in the game."
Tottenham's winless streak had seen a number of critics line up to criticise the Portuguese, who is looking to restore his reputation in English football after his failed reign at Chelsea.
Redknapp, who secured two top-four finishes during his time at Spurs, appears at odds with the type of management employed by Villas-Boas, declaring in an interview Saturday: "These days you're getting 70-page dossiers on this and that. Bull**** can baffle brains at times."
Villas-Boas brushed off the comments on Sunday, saying: "In the end it's not about the manager, it's about the players.
"Different kinds of managers have different leadership styles and the way they go about his business."