Samsung D800 - Not possible to get downloaded games working?

thor

I have been downloading games(using pcstudio) to my samsumng d800 but cannot get them to work. The files themselves are .jar and .jad types but when I try to execute them they come up as being unsupported. I tried googling for an answer but there does not appear to be one. In fact I've read that this might be a problem for samsung phones.
So are there any other samsung owners(particularly d800) owners who have come accross this same problem or is there anyone who has managed to get games downloaded and working? If so how do you do it?