In full agreement on Gundam- don't even think of cracking the shrinkwrap on this one. It is utter crap.
I wound up getting Full Auto 2 for Christmas but haven't tried it out yet- I'll probably start checking it out in the next day or two after we start clearing gifts out from under the tree.
I would say definitely keep Resistance and Ridge Racer 7- the others you will have to go on your feelings toward that genre. Gundam and Dark Kingdom, however, I would trade those in or eBay the suckers unopened.