Welcome to AA!
We always recommend a larger tank, as the extra water volume is more forgiving to the newbie mistakes that everyone makes. So, the largest you can afford is the best route to go.
Depending on the types of catfish, I dont' see a problem with your stocking list. For the pleco, though, you need to get one of the smaller varieties. The general common pleco will grow way too big for a 25g tank.
Take some time to look around. I highly recommend you read through the Nitrogen Cycle and Fishless Cycling articles, which are linked below in my signature.
Oh, and plecos don't eat snails, there must've been a different cause for their demise.
In the DC Metro Area? Check out GWAPA