Are you nuts dude!!! Do you realize how tough it is too crack source codes? Not impossible, but you have too be one damn good programmer too do it. Also, I'm not sure if Taldren would like the idea hacking into their source codes. I suppose Taldren would not mind if you did it for free, but if you cracked the source code I'm sure Taldren and Activision would be very unhappy as its their engine and they don't want anyone possibly stealing their work. Watch your head if you do accomplish this very difficult goal.
As for what language, I would guess SFC3 might have been built in VC++6, but its very possible that they used VC++.net. If they used the latter, VC++6 would be almost useless too you.
P.S. Just for the record, I prefer VC++6 and VB6 over the .net languages. The old languages take only a fraction of the resources and you can do most of the same stuff anyways.