There are many different types of polymer clays. I use ProSculpt which I buy from Jack Johnston's website: http://www.artdolls.com/
I think it cures beautifully in the oven without "moonies" and other marks in the clay.
Super Sculpey is nice beacuase it is available at Michaels and other craft stores. That is what I started out sculpting with. My daughters use Sculpey on their babies. There is also Fimo, and Premo which I think would work well too.