Took my gmat a last week and got a dismal 600! (Q-42;v-31)

.My initial thought was to retake the exam.I have been reading admission requirements at the college's website and found that range was from 650-750+.Iam not sure if it is for ppl who dont have a wk exp or for who have a wk exp.
I will have a wk exp of 5+yrs till aug'09. Does a score of 600 still suffice?What are the chances of being considered for interview given that i am looking at applying to Sloan,Kellogg and other top notch schools.
Please advice.!
Thanks
Vinay