Mario > Sonic. For the "ever bought a game for a reason other than the game" the closest I've come to it is buying a game just for multiplayer because a friend wanted to play it, which I'm not sure counts.
Bonus Question: What is your favorite “The good guys lose” moment in a game?
Picking a favorite "good guys lose" scenario would be like picking my favorite child-- you know, if I liked kids. It's really hard to do it incorrectly. If I had to pick one, it'd be that time Squall died, though. (never will I be silenced!) No in all seriousness the Tales of Symphonia moment I mentioned earlier (even if you don't recall the post, I'm sure you know the one) is probably the one, because these moments are always better with boss fights (that you can futilely beat with enough skill) to give you the illusion of hope.
Bonus Question: Have you ever had a moment in a game where you were so nervous while you were playing that you were shaking?
The shaking thing only ever happens with me when I'm going to lose a lot of effort if I screw it up and it's a pretty difficult section to nail down so the feeling that I could screw up is there. Diablo 2 Hardcore mode (one death and your character goes poof) is really good at this if you don't instantly vaporize simply because you put a lot of effort into your character and don't want to see that go down the drain when you're in trouble. Other stuff like tough bosses in a game like a Touhou or a Devil May Cry game can do it too if I've been working at it forever. Never happened from like, environment like you were talking about though.
--
No problem!
This is a cute and pop genocide of love!