Stupid me accidentally synced my outlook contacts to my ipad2. Now I have two groups, one called from PC. How do I delete the groups?

If it's an account, then turn off the syncing for the group you don't want for that account. Whne the popup asks if you want to remove contacts, say yes.

If you did this in the Info page of iTunes, uncheck the contacts sync box then go to the bottom and choose to overwrite the contacts on the iPad. Sync.