The usual culprits are:
1. Corrupted normal.dotm
2. Corrupted registry key (usually the Data key)
3. Misbehaving add-in.
For starters, try starting Word in Safe mode. Hold down the Ctrl key while
starting Word, and click Yes to starting in Safe mode.
If Word runs okay in safe mode, then I would try renaming/deleting
normal.dotm and renaming/deleting the Data key. If those don't fix it, I
would then begin to investigate add-ins, although, that will be difficult if
Word doesn't respond... so I hope that 1 or 2 will fix it.
Take a look here for additional information, including information on
editing the registry:
http://support.microsoft.com/kb/921541
--
Herb Tyson MS MVP
Author of the Word 2007 Bible
Blog:
http://word2007bible.herbtyson.com
Web:
http://www.herbtyson.com