Sounds like the starter contacts. It's a common problem with 4runner starters once they get up there in age.
You don't need a new starter. Your toytota starter is better than any aftermarket piece of junk. All you need is about $15-20 in parts and the time and tools to get that starter out.
Here's a linky for ya
http://www.toyota-4runner.org/3rd-ge...tml#post530199
Oh, forgot to mention I think the headlight part is just coincidence. If you keep trying the key sooner or later it will work. Shoot try opening a door and closing it and then crank the key. The vibration will probably do it.
You don't want to put this off too long though. They have been known to get stuck as in starter keeps starting even after you release the key...