I am looking for platformers in the style of the old Mario games, preferably free (or at least having a free version to try out first). Any suggestions would be helpful.
No store will take a trade in that doesn't work, so I am afraid you are stuck with the broken DS and PS3 controller.
Play N Trade does accept retro gaming items, but they must be in working order to qualify for trade in. Without an AC Adapter, the SNES is not in working order, since those cables...
It might not be on there for awhile. X-Box, for some reason, doesn't do day 1 digital games like PSN started doing. It actually takes some time (sometimes at least a year!) for a game to be available on the Games on Demand section of the marketplace.
It is possible that it will show up before...