It sounds like the windows installer is having trouble.
Likely, when you are opening RH there is something that needs to be
modified, (like word) using the windows installer, and it is
hanging.
First thing to do would be to check the Event Viewer and see
if you can verify that the installer is causing problems, or if
some other application is to blame. If it is the installer, or you
can't find the offending program, I would start with running the
installer cleanup. You can find it here...
http://support.microsoft.com/kb/290301
If you are still having issues, I would try to
repair/reinstall the installer. This may take a little more
research, but here is a link to get you started...
http://support.microsoft.com/kb/893803/
Hope this helps.