For parking come off at the Trafford centre/Trafford Park junction (2nd junction as you come over Barton bridge) and follow the road up up towards the swamp, few places to park up there for a couple o quid.

As for food, not too clued up that side without going into the city centre.
There used to be a nice place just 2 mins of J5 of the M61, Chequers restaurant, not been up that way for a while so could have changed.
As you come off the junction follow westoughton and you come to another roundabout, straight opposite is a row of buildings, its the last 1 on the right as you look at it.