byrdseyeviewinc,
There are rumors that new hires could start in right seat of anything from 727 to MD-11 or A-300. I don't know what to expect. I do know that new hires typically go to 727 FE seat. It all depends on what the company needs in terms of pilots in certain seats.
121 ground schools are like trying to drink from a fire hose. I have been through 4 at my current airline. If you stay awake while the instructor is teaching, and study a little on your own, you will be fine. Pilots tend to form small study groups to help each other with difficulties. If I can do it, anybody can!
Once you get to a 121 job, the company wants to keep you there. I don't think there is a lot of weeding out. Occasionaly, a pilot will wash out, but not very often. Good luck.