I love SSB! I mainly play it with friends, in vs. mode though. I started with Link, but can also play Peach (I was entertaining an 8 year old, and kept beating her. She was getting bored, so I tried to lose, but I can't just LOSE, so I used progressively worse characters. Peach wasn't that hard to use, but I eventually lost with Jiggleypuff). I have trouble running, and usually end up falling off cliffs, I like slow characters or characters that fall really slowly, like Peach. I always end up dying as Samus. Game and Watch is fun, but not very good.
"'You scoundrel, you have wronged me,' hissed the philosopher. 'May you live forever!'" - Ambrose Bierce
I own Melee and Brawl, and they're both awesome. I used Young Link in Melee, and in Brawl I use his "replacement" Toon Link. I really don't know how skilled I am, but with Toon Link I'm probably a level or two more advanced than the level 9 comp players (not sure that makes me a pro or anything though).
As for a "best type", I don't think there really is one; the best type for playing it usually depends on the types/strategies of the other players. To some degree, I think you can learn a lot about somebody's personality type by playing SSB and analyzing their attitudes towards and when playing the game.