Fighting Styles
Kick boxing is probably a good pick for beginners, followed by Streetfighting then either Wrestling or Submission as a third choice. Martial Arts sounds neat, but is fairly hard to KO people without a blazing grapple or an environmental-based throw (like head into a TV set).

Rewards Points
Go to the cheat menu in extras and enter the following codes:

100 reward points: CROOKLYN
100 reward points: NEWJACK
100 reward points: THESOURCE
100 reward points: GETSTUFF
100 reward points: DUCKETS

Song: Afterhours by Nyne
Enter LOYALTY as a code

Song: Anything Goes by CNN
Enter MILITAIN as a code

Song: Bust by Outkast
Enter BIGBOI as a code

Song: Chopshop by Baxter
Enter CHOPPER as a code

Song: Comp by Comp
Enter CHOCOCITY as a code.

Song: Dragon House by Chiang
Enter AKIRA as a code

Song: Get it Now by Bless
Enter PLATINUMB as a code

Song: Koto by Chiang
Enter GHOSTSHELL as a code

Song: Lil' Bro by Ricbyobyche
Enter GONBETRUBL as a code

Song: Man Up by Sticky Fingaz
Enter KIRKJONES as a code

Song: Move by Public Enemy
Enter RESPECT as a code.

Song: Original Gangster by Ice T
Enter POWER as a code

Song: Poppa Large by Ultramagnetic MCs
Enter ULTRAMAG as a code

Song: Sieze the day by Bless
Enter SIEZE as a code

Song: Take a look at my life by Fat Joe
Enter CARTAGENA as a code

Song: Walk with Me by Joe Budden
Enter PUMP as a code