I'm usually frantic - weighing the suitcases, taking stuff out, asking the kids if they really need 4 pairs of trainers each...

I'll also be charging up the batteries for the camcorder, digital camera, mp3 player etc.
I make sure I do all the washing and ironing, so that when we come home there's plenty of clean clothes to wear and just our holiday clothes to wash. I cut the grass, clean the fish, water the plants, put spare milk and bread in the freezer (milk goes in ice cube trays ready to pop into a cuppa when we get home), set the light timers, set the video, clean the kitchen and bathroom and put nice clean fluffy towels out for a nice soak in the bath when I get home.
In the evening before "H-Day" I'll have a long bath, de-fuzz, pluck eyebrows, apply fake tan, file & paint nails and get clothes ready for morning.
The tesco idea is a good one, might think about that one this year, although I'm not sure I'd be up to unpacking a big food delivery as well as having the usual piles of washing all over the kitchen floor