Smartboy software currently does not support multiple games per cart with a selectable menu. However, I talked to the guy today and he said they are already working on free software that will allow you to do this.
I hope it's ready soon... like before mine gets here
you should contact the folks yourself as well to turn up the pressure on them and I will do likewise and say I won't buy one until they get that software done..
going to do that now...