DW and I are in the process of moving right now. It's a 350 distance and we've done it all ourselves. A few pickup loads and two 12' U haul trailers.
Travelover has some great advice. If I had it over I would have gotten rid of most of the big furniture and started over with new stuff at the new location (sofas, recliners, mattress & box springs...) You may want to buy furniture that fits your new place anyway. Tell your kids to get their stuff if they have any at your place, don't move it to your new place. I was surprised how much of our kids stuff we still had even though they moved out over 5 years ago. Lots of games, books, VCR tapes....
Consider hiring help, at least to load and unload. DW and I did it ourselves and it was stressful on us.
We sold all the appliances with the house, except the freezer. I should have included that with the house too. I gave the buyer whatever property they wanted with the house, so I got rid of the gas grill and push mower.
Sort through your papers now. Don't move anything that will get thrown away at the new location. I am ashamed to say that I moved a lot of stuff that is going to go in a dumpster at our new location.
If your selling your current home, I would hire an inspector to come in before you list it with a realtor. Then you can fix the little things BEFORE the buyer's inspector comes in and cuts your place apart. Having it inspected will give you more leverage in any negotiation that comes with a house sale. Start getting your house ready to sell now. Make sure the mechanical, wiring/plumbing and roof are all up to date. It makes your house much more marketable if the buyers don't have to do anything. They will likely paint it and update the flooring anyway. Just make sure you have neutral colors that any potential could live with.
Get a good realtor, start interviewing now. Look at their ads like you are a potential buyer. Its not too soon to start contacting them with your plans.
Try not to accumulate too much groceries in the last year. It makes no sense to move a whole pantry, fridge & freezer contents.
Don't move when its 30 below zero.
Good luck to you.