.NET 2.0 vs. IIS?!?!?!

(sorry for my poor english)
Hi everybody....
I have a little problem.... I have already installed:
- Windows 2003 Server
- IIS 6
- .NET Framework 1.1
- Visual Studio .NET 2003
and when i install VS.NET 2005, the windows IIS Manager don't work, when I try to open the Properties of a WebSite item, it throws an error and close it... if i uninstall the framework 2.0, it starts to work again....
I tried it on Windows XP Professional and happened the same,
What am I doing wrong???

Thanks!