This game is another one of my favorites of all time. If you like games such as Guitar Hero you will love this game. The music is great, and it also has anime video's in the background. I find it fun because I personally am a great music fan and hearing the difference when you hit the buttons on the right time compared to missing it makes you get into it.
Theres a large number of different genre of music to play and you can also select from 4, 5 or the hardest - 6 button mode. It's a cool thing to show off to your friends when you get real good at and they will be wowed.
As far as the differences in part 1 and part 2, the only thing really is in part 2 you have a meter that can double your points as you go without missing any notes but other then that it's basicly just different music so get both if you can afford too.
If you want a game that you can play again and again without getting tired of it then I would recommend this game, and also recommend it to all you music/DJ fans out there.
Features(DJ MAX 2):
# Over 60 original songs
# 5-button mode
# New "Fever" mode
# Easy mode, for beginners
# Soundtrack across 4 discs -- the "most DJs in the history of gaming"
# Over 500 hidden items
# Linkage with DJ Max Portable for owners of the first game -- play the original songs using the new play systems
# Korean, Japanese, and English interfaces
# Remote control support -- use DJ Max Portable 2's Soundtrack Mode to enjoy songs whenever and wherever
# Customizable control configurations
More information:
DJ MAX PSP - Google Search