Earlier this year, I had issues with my old XP gaming rig which had ET. I just copied the whole ET folder onto my newer Win 7 computer. When I ran it the first time, the resolution was wrong; I assumed this was due to the new video card environment, etc. But on running it the second time, it work normally. Admittedly, there's no uninstaller in the Programs and Features Control Panel now, but I don't plan on uninstalling it.
So if your USB stick is big enough, you could try just copying the whole folder.