Hi neighbour!
If you have young children who don't want to ride the big rides, take advantage of the baby swap. One adult waits with the child whilst everyone else rides, then you swap over so the other adult can ride with someone.
If you're getting FP's for the bigger attractions, use all the tickets (even for those who don't want to ride) and then someone can ride twice if they want to.
Book meals waaay in advance. Not everything, just the things you really want to see, because you might struggle getting into restaurants with a party of 8!
Plan a break for the middle of the day. If you're faced with tantrums, take a break. Don't force people to be out any longer than they want to be!
There are some rides you should try and hit first before a line appears. There can be REALLY long waits at the following:
Epcot - Mission Space, Soarin', Test Track.
MGM - Rock n Rollercoaster, Tower of Terror.
Magic Kingdom - Winnie the Pooh, Peter Pan, Space Mountain, Splash Mountain, Buzz Lightyear's Space Ranger Spin, Pirates of the Caribbean.
Buy the Unofficial Guide for 2007 too. It's full of hints and tips and we love it.