This has been discussed a lot, for some good background and other ideas, do a search.
FWIW, I ride Vittoria Rubino Pro Slicks, and am very happy. On a better set of wheels I have Vittoria CXs, wonderful ride, but not very long lasting. Ah, trade-offs...
Having said that, I am not sure they come in x25s, but you can always ride 700x23s and will be fine.