Rock,
The 737 and 75/6 perform mostly trans con flights to the Eastern Coast. Some rotations link through SLC. We used to do a lot of Mexico and still do a little up the west coast, but as others have written, much of that flying has been outsourced to our codeshare partners.
Very hard to guess how long it would take to hold LAX. Right now the junior person on the bid is a 11/2007 hire.