DJ Campbell's goal ensured McCarthy began his Ipswich tenure with a victory after Town went into the match bottom of the table and winless in 12 successive matches in all competitions.
McCarthy was delighted with his players' efforts, although he delivered a sobering message to them following the victory.
McCarthy said: "You couldn't have asked for much better than first game getting a win and ending a losing streak for the club, and a losing streak for me.
"My last game was a defeat (as Wolves boss in February) and I didn't want to start with one.
"I thought the players gave everything. We had some blocks, there was a great save at the end. I thought their goalkeeper made a great save from Danny Higginbotham.
"All in all it was a fairly even game, I think we deserved to win it and the block and the save at the end earned it for us.
"Afterwards I went to give the players a pat on the back but I gave them my usual caustic soda.
"I just said to them you should be embarrassed that you're bottom of the league. If they'd have worked like that, played like that and blocked things like that then I wouldn't even be in the job."