I usually use the following order, which goes from larger muscle groups to smaller:
circuit (with back and legs)
chest
leaner legs (to give the shoulders, which are worked during back and chest days, a break. If you put your rest day somewhere betwee back and chest or chest and shoulders, then you could do shoulders here and leaner legs later).
shoulders
triceps
biceps
(though the back is technically larger than the chest, and the triceps larger than biceps, the difference isn't that great, and you could switch these up, just remembering--as someone already mentioned--that you need at least a day off between the circuit and the leaner legs workout)
I actually like to double up on some of the weight workouts, doing shoulders on their own:
back/chest
day off
shoulder
leaner legs
triceps/biceps
You could also do a back/biceps, chest/triceps, leaner legs, shoulders rotation with CTX