There is a setting by which VS debugger decides how much time to wait before time out exception occurs. One can override this value :
HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\9.0\Debugger
At above location in the registry you will find two keys :
1. NormalEvalTimeout
2. QuickwatchTimeout
You need to change the values for these keys. The value for them is in milisecond.
Default Values :
1. NormalEvalTimeout : 5000 ms
2. QuickwatchTimeout : 15000 ms
Hope this helps.
All the best.