iPhone and iPad - moving backups/syncs between computers?

Quick question. I have an iPhone 3G, but will soon-ish upgrade to an iPhone 4. I will also be getting an iPad in the next couple of weeks.

Currently I am syncing to my mediacenter PC in my livingroom. This is scheduled to be replaced in the semi-near future as well. How do I move my syncs/backups between PC’s? Do I just copy the iTunes folder or is it stored elsewhere?

Also, when upgrading to an iPhone 4, do I just sync my 3G and then restore the 4 from the same backup?

Yes and yes.

Thanks and Thanks Xpav.