I have 1 bike with 700x25 and 1 with 700x23's. As others have said, flats are a fact of life with cycling. I recommend practicing at home so in case you do get a flat, you're prepared. When I first changed a tube, it took me FOREVER. Now I can change a rear flat in under 10 minutes. Part of that reason is I got a lot of practice this year commuting. Lots of glass on the road. I use kevlar tires now, which has helped. I've noticed that performance bike's tubes aren't that great. I think some of my flats were from a failed valve stem versus a hole. I haven't taken the time to look them all over though. I have a continental gatorskin on my front tire and michelin erilium kevlar tire on the rear of my Trek 1200. Both are 25's. On my Lemond I have vredestein fortezza SE's, which are 23's. Those are higher peformance. I use the Trek to commute. Other than tubes, having a good frame pump is key also. Topeak makes good ones.

Hope that helps.