If you're unfamiliar with carpets, I would definitely recommend staying away from them.
Personally, I would go with a bubble tip anemone. It has been said that ocellaris will not host them, but I believe many people have had success. Bubble tip anemone's are relatively easy to keep compared to other anemone's, too.
Keep in mind, though, anemones are not easy to keep. The require good water parameters and relatively stong lighting.
Good luck!
-Scott