Please give some more information, like what game you play and in what situation they freeze.
I don't use RTS very often, so luckily I haven't got any problems with it.
If you use an emulator for your SNES on your DS, you should be able to play Super Mario RPG.
The games I'm waiting for are basically Nanostray 2, A new zelda, could be a N64 port and something like hotel dusk 2
Trauma Center
Phoenix Wright - Ace Attorney
Another Code 2
I'm working on Nanostray, I think the challenges are very nice to do because they are so hard !