Agree with cleaninglady, especially to get the packers in, you will not begrudge a penny spent and compared to all the other costs of moving it is peanuts.
Ask about the company's policy on emptying lofts - some refuse to go up and bring stuff down and you must you do it yourself.
Read your meters as you leave and phone them through to the utility companies - most have a homemovers number you can ring in advance to set up the details of your move. Do the same when you arrive at your new house.
Don't forget to have sugar to go in the removal men's tea, they seem to expect a cuppa every hour and a little snack doesn't go amiss if you want your stuff treated nicely! My DH always makes them bacon sarnies, even while they're trying to pack up the kitchen (but i wouldn't recommend this!)
If you can take the kids to see the new house before the move so they have an idea of where they are going, ask if you can take some photos of their bedrooms. We went to ikea to choose some bits and bobs - new bedside lights, duvet covers etc for 'their new room'.
Try and plan where all the furniture is going so you can stand in the front garden directing the men as it comes off the van.
Don't get too depressed when you open your new front door and see your new house looking sad and empty and probably a bit grubby. By the end of the day it will be stuffed to the gills with your stuff and hopefully, after a takeaway and bottle of wine, will feel like home.
Oops this is a bit long - Sorry if anyone's fallen asleep.