Thanks guys, I'll just keep the Mongoose for now until the repairs become unbearable or something. Although my brakes work fine now, is there anything I should replace asap before it breaks? What do I replace them with, Shimano?

Also a question: it's against California law to ride the bicycle on the sidewalk apparently (not pedestrian), but if there's no bike lanes and the curb has parked cars all over, how am I supposed to ride inbetween the parked cars and cars coming from behind me (right side of road)? I'd rather not want to get to close to the parked cars in case I wobble and crash (or run into an opened door) but passing cars might be too close for comfort. That and the need to get better with turning are the main reasons I haven't rode out of my neighborhood yet.

Thanks.