I would recommend doing squats, power cleans and deadlift, as well as plyometrics.
For plyo (plyometrics) i would suggest the following exercises:-
Squat Jump
Box Jump
And if you feel inclined to do some upper body plyo, you should try depth pushups and plyo pushups.
Plyometrics focuses on bust strength, perfect for martial arts. Power cleans also focus on a lot burst strength.
Squats and deadlifts are good for developing the strength in your legs and core. For martial arts, I wouldn't recommend doing things like leg press and things that have the path built into the machine, because it removes your stabilising muscles from the workout.
With regards to squats, deadlift and power cleans, you really need to spend a good few weeks working on your form, otherwise you can hurt yourself very very badly.
You also need to make sure you have a good stretching session after lifting weights.
Just my $0.02
P.S. I started martial arts about 2 months ago, before that i spent about 4 and a bit years doing body building. Since i started martial arts I have basically stopped the body building, and started training weights for strength, power and endurance, as well as to maintain muscle mass.