Unless you are going to the Arctic Circle, heading north shouldn't really change what is involved in the aiming of the dish....though maybe what was being said, was that you'll have more trees and such to contend with, because the satellite is lower on the horizon?
Your HD TV will show regular programming just fine, and unless you have to watch HD, why bother. Are you going to be full-timing, or just going on vacations? If this is just a vacation, or weekends, you will probably find out that you won't be watching as much TV, and why make it more of a hassle?
All that said, if you've got the HD Box, and that is what you plan to bring with you, you might as well just get the HD dish, and spend some money on a compass and elevation device to help line things up.