Some other points:
1. Although many have mentioned getting to the airport early and grabbing exit row seats, consider avoiding these seats to be certain you don't get some evil kid kicking the back of the seat all flight. Kids infiltrate this route in all classes

, and i'd therefore consider going for one of the back rows, either in the first or second section of the upstairs PE cabin.
2. If you go for Hertz for car rental, you can get the nifty Neverlost satnav system, but you'll need to get a transfer bus outside the airport to the Hertz lot. If that's too much effort, go for Avis who are on site. They have a somewhat inferior satnav system, but you only have to go down the escalator from the bag reclaim to get to the desk. Both will give you 1000 FC miles, which is surely the most important thing

.
3. Have some dollars ready for the tolls if you are taking the Beeline Exressway or the Central Florida Greeneway from the airport. Avoid the I4 as much as possible, as there may still be crowds about in September and traffic gets heavy.
4. Eat as many Krispy Kreme doughnuts at the airport as possible on your way home - you will miss these when you are back in the UK unless you can be bothered to hunt out one of the new stores popping up all over the place back here (side tip: Bluewater shopping mall has a Krispy Kreme outlet and an Apple store, thus reducing the need to visit America quite so much...[8D])
5. Enjoy ice cold Bud on tap in the Delta Crown Room. If you don't have a Gold card/Priority Pass, beg steal or borrow to get in there (or I think there is a way you can get in there by paying..).
6. Priority boarding works at MCO. It's to the left of the normal boarding area. Use it, then wonder why VS can't sort this out at LGW [:p]