Here's a few things to try:
Go to MyDocumets/EAGames/TheSims2 and delete groups.cache, cigen.package, and ContentRegistry.  Give Bodyshop a try.
If it still doesn't open, then go back to MyDocumets/EAGames/TheSims2 and move your SavedSims folder to your desktop, then try again.  Once you're done with Bodyshop, move the contents of your SavedSims folder back into MyDocumets/EAGames/TheSims2, Bodyshop will have created another SavedSims folder there.
The SavedSims folder usually is the problem, unfortunately I don't know why. 
 Here's a link to some useful BodyShop information:
http://www.sims2wiki.info/wiki.php?title=Game_Help:Body_ShopI hope this helps, I love the Sims you upload here on Insim.  :daisy: