Visual Studio can nicely be uninstalled, but you need to use the main setup for this. Do NOT try to uninstall it's dependencies on your own. It will take care to remove the installed dependencies fine.
I had VS 2003, VS 2008 and VS 2010 installed (in that order). Then I uninstalled VS 2003 without problems, with VS 2008 and VS 2010 still working fine.