"2. The Trac Off light comes on."
I had this happen over a year ago for about a month, off and on. It stopped happening without any repairs and hasn't happened since. You MAY be looking at more than one issue, although when you put the car in reverse, all the problems go away.
You may want to start looking at patterns of when this happens, outside temperature, how long the vehicle has been sitting, are you starting it in the dark and does it only happen in the dark, anything that can begin the isolation process. Since it doesn't effect your reliability, safety or performance- seems you have time to work this through.
2001 Bonneville SSEi, 219,000 miles.
Whats in my driveway:
1998 Chevy S10 4x4 ZR2, 1999 Olds Bravada, 2001 Pontiac Bonneville SSEi, 2007 Ford F-350 regular cab 2WD, 2008 BMW 335i coupe (Wife'* replacement for her Bonneville). The Bonneville is my favorite of all the cars in the driveway.