1. It has more options but NSMBwii has more replay value
2. What level you move from cog to cog?
3. I play both with nunchuck and both work great
4. I have to agree.... I hate that I work all game co-op and I die last second before the finish line, my sister and cousin panic and they both enter to the bubble
5.
a) You'll be laughing so hard you won't care
b) that's pretty anoying, but there's pick-up and carry and if he/she slows you down just throw him on lava