Yannick Bolasie hit Palace's winner after 13 minutes, but it was Speroni's string of superb saves - culminating in deflecting Conor Sammon's 87th-minute spot-kick on to the crossbar - that eventually earned the Eagles a first away win since November.
"I think he's a wonderful person," said Holloway. "It's not just what he's like with his gloves on; he's a wonderful human being.
"I think he epitomises the club - we're fresh, we're hungry, we want to do it. He's been player of the year three times in a row so he's definitely a fans' favourite, and he was absolutely outstanding.
"It's nice to get that monkey off your back and it took a marvellous save from our goalie - I thought he was inspired.
"That's why he's got his own bar at our ground. To do well you need a really good goalie and he's proved that tonight."
Holloway sympathised with Derby, adding: "They've had a lot of bad luck. They've got a young side who are so enthusiastic and they probably deserved better than they got, but we've got to take that and try and move on.
"We all looked a bit nervous at the end, myself included, because we want it so bad.
"I'm going to enjoy this because we're in with a shout of automatic promotion and that's fantastic for everybody at the club."