Ok I've decided. I'm gonna sand the whole frame down with 800 grit, and then what? I'm gonna paint the whole thing myself but I'm not sure what kind / brand paint to use. I'd like for it to be more durable than whatever comes in those cans at Home Depot. Do I need to head down to the local auto paint store? I don't mind buying a new paint gun if I have to. Should I be looking at using an enamel?

edit: Just got word back from my bike mechanic buddy and he said he's used Rustoleum metal paint in a rattle can followed by a clear and it's held up for him really well. Says the paint has come a long way, so maybe. Any advice along this direction? Seems like it'd certainly be the cheapest, and that's good with me.