You need to install the following below in the following order to get VS 2005 running properly on Windows 7.
1. VS 2005 SP1 - http://www.microsoft.com/download/en/details.aspx?DisplayLang=en&id=5553
2. Visual Studio 2005 Service Pack 1 Update for Windows Vista - http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=7524
That's all. Enjoy it~