Every branch will guarantee a job... just depends on how badly they want you. I was enlisted Navy before I went to college and my job there was gauranteed. A contract is still a contract, and that is what you are signing when you enlist.
The Air Force is still cutting certain jobs, so a green to blue move is pretty unlikely (although they are still trying to sell blue to green).
What sort of degree? An associate's is pretty much expected after a certain rank for promotion purposes, especially in training jobs. If you are closing in on a bach, then don't enlist, you will just end up kicking yourself... unless you WANT a lower paying, more menial job...
02 WRX Cobb Stage 2 now SOLD to my father who sold it to my Brother. Have fun Al!