With my particular phone (Droid2 Global) you can't root if you've upgraded to 2.3. Nor can you downgrade to 2.2 and then root. Basically I'm just stuck on castrated Gingerbread for the life of the phone.
I'm sorry. That's lame. I recently (finally) got my wife's phone rooted, and it was a pain. The whole experience has me considering writing a scathing critique of the the whole "just root it" culture of Android, which is, I have to admit, very similar to the responses here of "just wipe and do a clean install". It wouldn't be so bad, except that there is so much unintentional disinformation, broken links and general nastiness in trying to prevent people from messing with their own hardware. I've had easier times developing embedded software with sh!t BSPs! I blame not just the manufacturers (Samsung, I will never buy an Android device from you; between rooting my wife's Samsung phone and the Tab from work with it's non-standard port and refusing to charge off anything but the supplied charger, just no), or even the carriers, but the community really needs to get it's sh!t together.