I have not ever seem such an issue before and now that there is no specific error in log, I think this may not be easy to directly point out the cause.
You may verify whether all agents have been applied VS2008 SP1, do remember that you have to re-apply SP1 if you install controller or agents on machine which has already applied SP1.
If these all not help, you may take the following steps:
a) Try to run devenv /ResetSettings (in command prompt) to eliminate the related potential settings problem.
b) Try disabling Add-ins (e.g. “Tools” | “Add-in Manager”) or run “devenv.exe /SafeMode”.This can eliminate the possibility that third party Add-ins or packages are causing problems. (For more detailed
VS command line switches information, see:
c) Try creating a new project. Sometimes corrupted project settings can cause problems. These are project specific.
d) Try to reboot the operating system to safe mode. This can help to isolate whether any other applications are interfering with Visual Studio. Note that some features (like IIS) are not available under safe mode. Please check whether
this can be applied or not. In addition to safe mode, we can also try “clean boot”: How to configure Windows XP to start in a "clean boot" state
e) Try to create a new user account. This can help isolate user profile corruption related causes.