2004 Ford F-150 sudden Rough Idle

Shakes or Wobbles problem
2004 Ford F150 V8 Four Wheel Drive Automatic 95K miles

I have a 26 mile commute to work daily, as I neared my destination, my truck began to sound like a deisel, shaking and shuddering, with a squealing from under the hood, but it never fully stalled. I made it to a parking space where I let it sit for at least 2 hrs. Checked the oil and water (both fine) started the truck, (started fine) but the squealing was there immediatley followed by the rough idle, (ac off). I had it towed home for fear of possible damage to the engine.
The next day I started it, with no squealing, just the idle going up and down, and nowhere near as rough as it was, but I did not let it get hot like the drive to work would have.

I figure the squealing could be a pulley possibly seizing up, but wasn't sure if that would cause such a crazy idle.
I purchased a code reader that did not work, so I returned it. I plan on getting another but I have to wait for a payday.
I bought this truck new, serviced regularly, and this is the first real problem I have ever had.

Thanks in adviace for any help and a truely fantastic site.
Russ