You may have a corrupted outcmd.dat file.  This is the file that stores your
toolbar customizations, and when it becomes corrupted, Outlook can't use it
at startup to build your toolbars, thus causing the hangups.  Try renaming
or deleting your outcmd.dat file while Outlook is closed.  Renaming it might
be the best idea if you have a lot of customizations that you'd prefer not
to lose; that way if renaming the file doesn't solve your problem, you may
be able to restore it later when you do get Outlook working properly again.

Note:  If you're using Windows 2000 or XP, you'll need to search in hidden
and system folders to find the outcmd.dat file.