Took it for a spin...not good

Well, I decided that today.. after months of sitting in the garage i'd take the stang out for a spin. I put in the gauges so i could monitor temps and speed and all... at first she ran great, but 5-6 minutes into it, i looked at the temp gauge and it was all the way on H (i was going up a hill... so i decided to turn around and go back down home... So i pull into a drive way, and put in reverse and press the gas... sputters, get a click kinda noise and it stalls, hit the brake, turn the ignition, she starts up. head down hill, and notice the speedometer stopped working, going up it bounced around but worked, now it just completely stopped
pull into the driveway, and try put my hand under the dash and up to the gauges to see if the cable for the speedometer just came off, couldn't get it, the car then starts to spit out a bunch of steam... I turn it off. Open the garage. Turn it back on, it turns over real slow, put it in gear and press the gas and it sputters and clicks and dies again. try it again... same thing... wait a few minutes and try... it works...

What would cause this? I know i need a new radiator... (the current one has gashes in it... and its spitting out steam...) The click i'm describing is like in the movies when a car dies it sounds like something is rattling and then dies..

gah! i was afraid of that, hopefully no other damage. Its weird before sending it off to paint the car was perfectly fine... Then i started redoing the wiring and all.

Any recommendations on a new radiator? It's a stock 289, no hipo, no modifications. Should I get a standard 3 core? 2 core? aluminum?

I live in southern California, so no extreme weather, summer can get kinda hot.

I'm pretty sure the battery is close to being dead, a combination of things happened, first i installed a new stereo (including sub) without upgrading alternator, so it sucked out some life of it, then while i was working, the courtesy lights were on a lot.

Ugh! starter =\! i know i have to replace it, i get a metallic screech every once in a while, and the mechanic said that that means either a new flywheel or starter or perhaps both; but he said enjoy it and drive it until it gets to the point where u can't start it anymore...

gosh... the list just keeps on going and going... it all started in june as a simple clean up the wires job... and is turning out to be a close to full restoration.

I have not touched the engine yet... so I have no experience with it at all, how can i tell if the heads are warped or if a head gasket is blown?
Would I be able to drive her down to the local radiator shop? (5-6 miles away)? or is better to trailer it?