I am so deppressed,PLEASE HELP?

im am so depressed. i have a very low self esteem, i find school really hard, before i used to get A and B, now I'm to the point that im about to drop out, so my mom took my Xbox 360 away. i tried really hard in school so i can get it back, and i suceeded, i got Bs and Cs, but my mom still wont give me my stuff back, i felt devastated.she has had my stuff for 4 months now. i can't do anything in my house except go on the computer, and watch TV. before you say that I play too much xbox, keep in mind that its the only thing my parents actually let do, BTW i play for 3 hours, 4 max. my parents barely lets me go out with my friends, yet i do a lot of chores, Ex. Clean my room, take out the trash, give my dog a bath, do the dishes, and sometimes i wash their car. kids in my school always pick on me. they always call me short, ugly,stupid, idiot, retard, midget, dumbass, which makes me feel horrible about myslelf. even when I try to play a sport, they never pass me the ball, even when im open. when i finally get the ball, everybody's like "WHY DID YOU GIVE IT TO HIM?!", or "YOU SUCK!, or "YOU KNOW HE'S GONNA MISS!", it makes me feel worthless about myself. I always think to myself, "would everybodys' life be better without me?". PLEASE HELP