Another vote for Master and Commander, not only the battle scenes but also when they beat to quarters, you can hear everyone scurrying around on the top deck from beneath, sounds like they're right above your head in the room.
Any of the Lord Of The Rings movies have great soundtracks, The Haunting, good wrap around effects. Matrix Revolutions has awesome use of the surrounds when Neo is speaking with The Source or mainframe. i, Robot has some good surround effects to it. The second scene in Saving Private Ryan when they're landing at Normandy has incredible effects as well.
Lots of the higher budget animated movies have excellent soundtracks and surround usage also, such as The Incredibles, Finding Nemo, Chicken Little, etc... -TD