I've beaten all the events, unlocked all teh characters and levels, plus I've gotten all the trophies you can get from the slot machine.
Here are some interesting things I know. Event fifty one is the last event, which can only be obtained once you've beaten all teh other events. In their you have to beat Giga Bowser, ganondorf, and Mewtwo. They re very tough and th eonly one character who can beat them is, unbelievably, Jigglypuff. His rest attack makes quick roadkill out of Giga bowser, and then the other two is just a mtter of getting anough distance to use rollout.
Something more. If you reach the end of adventure mode on normal or higher wihtout continuing and under a certain amount of time, you'll fight giga bowser after you've defeated normal bowser, and then if you defeat him without having to continue, you'll get the giga bowser trophy.
If you beat adventure mode on hard or higher wihtout continuing, you'll get the Crazy Hand trophy.
If you beat classic mode on Hard or higher, you get the Master Hand trophy.
Being a Pikachu master on SSBM, I thought I would give some help to those who just started. :)