I had such behaviour in MS Excel once... but I cannot remember how I solved it (not that I believe that VS .NET and Excel have something in common when it comes to menu-config)...
I think you can get back to the defaults of VS.Net 2003 (this is the version you use, isn't it?) by deleting these two directories (typically on the same partition as your windows installation):
<Documents And Settings path>\\<your logon name>\\Application Data\\Microsoft\\VisualStudio\\7.1
<Documents And Settings path>\\<your logon name>\\Local Settings\\Application Data\\Microsoft\\VisualStudio\\7.1
I assume that VS.Net 2002 would use sub directories named 7.0.