I swear it's nickel and diming me, but I still love it!
Now it's new thing is that when I go to turn on the car, it acts like the battery is dead, and the security light stays lit on the deashboard. I have checked the key, and the Black "thingie" with the metal wire is intact, although the key is a little bent. This time though, I just sat in the car and waited before calling for help, and I noticed that with the key out, the security light stayed on.
After awhile, the light went off and I figured I'd give it one more try, and it started as if no problem. So either I need a new key, or there is a problem with the security system. I am hoping key, since that seems to be the cheaper/easier repair. Any ideas?

If it's the very old system with the bump like thing on the key. That is only a resistor matched to your ignition. Nothing fancy.

Problem is, you cannot tell if it's the key or the ignition.

I'd check it with an ohmmeter while wiggleing it. I'd try some contact cleaner in the ignition switch and the ignition, but I'd get at least another key made. They should not be $100 or more.

Do you know what readings I will get with the ohmmeter? What should be normal, in other words?

Not off the top of my head, but here is a description;

GM VATS Pellet Inserted Chip (http://www.drdetailshop.com/gmpellet.htm)

You can check the chip and probably the contacts.

At this point you can look for instabilities.

It might be best to identify the wires from the ignition switch and measure there.

You have the key being suspect because it's damaged and you have the contacts in the ignition switch being a possible problem and you have the possibility of dirty contacts.

Wear on the side of the key is probaby the most likely. Followed by crud on the contacts. Followed by an unstable resistor.

You could "measure it" and then bypass it. Or you could by the kit and bypass it. By measuring, you don't know the tolerences expected. Although you could imperically find that out by using a potentiometer and the binary search technique.

Here is some more info about the system. Measure and by pass. http://www.911locksmith.com/gm-vat-keys.php

Here is some more info. The real fix.

New lock and key.