oh if you're gonna be driving it around town, then yes you need to register and insure it.
btw, if you can after you buy the car, ask the guy if he can put an amount on the transfer paper that is less than the amount you actually paid for it.
example, i paid 2500 for my car, and reported that i paid 1300.
this is so when u register, it will end up costing less. (still ended up costing me about 120 bucks tho).