Hi enggr,
It’s so strange that repair and reinstall Visual Studio also cannot fix the issue. Have you tried to test in Windows safe mode and run Visual Studio with safe mode?
Restart Windows and in safe mode, run devenv /safemode in Visual Studio 2005 Command Prompt.
If in safe mode this issue disappeared, the cause should be third-party applications, services or Visual Studio Add-ins.
Please also try devenv /resetsettings or devenv /setup in Command Prompt. And I would like to know how you reinstall Visual Studio. Have you gone through this link before?
http://support.microsoft.com/kb/907965
I hope they are helpful.