1990 90 CS Erratic starter and RPM problems!

[JesseTsi]

I got my car July 7th 2007 with 100,000 miles on the dot. It now has 106,000 and was running perfect, everyday with no problems other then the usual valve tick.
So the other day I am driving, and my powerband is usually 4K and up in the rpm's. There was hardly any power through the rpm's till about 6K. So just to be safe, I did a budget tune up (spark plugs and air filter) and I am having the same problems (at random times) sometimes it acts perfect, others it has no power.
Thats my first problem... but my second one could tie into the first one.

My starter is staying on after the car starts (for about a second or 2) but you definitly hear the grind. (this started today) Now when I turn my car off, and take out the key... THE STARTER CRANKS OVER . And when AI turn the key to the far left (where it should be in the off possition and release my key) the starter cranks over and will not stop untill the key is in the "accessories on" position.
10 minutes ago I just walked out to let my dog poop and my cars starter was turning itself over NO KEY IN THE IGNITION.

Could the starter be engaging while I am driving to bog my rpm's down? (I dont hear the starter crank over while im driving) Do I need a new starter ignition switch?

Any help would make my day... School makes it so I cant afford to see my friends at the Audi dealership

Thanks,
Jesse
Seattle, WA