The Wales international's third goal of the campaign settled the Villa Park clash and gave the midlands club revenge for a 6-0 mauling by the Magpies in August.
It also moved Villa five points clear of the bottom three as they survived a late rally in which Brad Friedel made two fine saves to deny Peter Lovenkrands an equaliser.
Houllier said: "I think we deserved it. We showed desire, commitment and fighting, battling qualities, which are a must in this sort of situation.
"Maybe we weren't enough relaxed at times but I think that's down to the pressure. When you have pressure, the team fighting spirit plays a big part. You can't have egos or someone who has lost the plot. The team performance comes above everything else.
"I thought they all worked for each other. There's a distinction to make between working together and working for each other. The effort of everyone was fantastic."
Source: PA
Source: PA