I work on a small web team where I am the only .NET developer currently using Visual Studio 2008 Professional to build and maintain a few web applications. I am about to st
Definitely, as most people says, Subversion + VisualSVN.
VisualSVN is a fairly cheap addon at $49, subversion is free and very stable. We use that for teams of 10-15 people and it works really well for us. The only con is that it is file-system based.
On the other hand, if you have a very specific need for it not to be on the file system i would NOT recommend Visual Source Safe, on my last job we had a lot of trouble with it and lost precious days of work. If you want to go that way get something like sourcegear vault which is database based. There is also Team Foundation Server from Microsoft but I believe it is really expensive (and heavy) for small teams.