1996 Oldsmobile Aurora

Maybe I can get a little help on this board.  Here is a quick back story.  I traded the car in the title to my mom in law.  Told her it was a premium gas motor and she ran cheap gas in it.  She was constantly calling to tell me that the Aurora was dying on her, so I traded her the Taurus back(going against me wanting to be selfish because I had the Taurus sold and was going to buy a Jeep I wanted).  I took the car to advance, hooked up the scan tool...check engine light will always be on because of an internal speed sensor...but I wanted to see what other codes kicked on.  There were 12...4 dealing with both upstream oxygen sensors being toast.  4 dealing with maf sensor(which is now new along with tps).  A knock sensor, multiple misfire...a lean oxygen code, and the speed sensor.  OK...car runs like poo...I pulled a couple spark plugs to see what they look like..little carbon build up, but they were orange looking..almost rust color.  I am gonna replace plugs because I am looking to trade it off...all I want it to do is run correctly through Saturday...am I overlooking a different possibility for it to run crappy.  Goes down the road fine, its when it idles...chugs between 500 and 750 RPMS.  then dies...but starts right back up...and I have a very noticeable vibration when turning right...whether turning on the move, or turning while parked, not a grinding noise...heavy intermittent vibration...any ideas on quick inexpensive fix?