With me, TF2 doesn't give me any problems, whereas HL2 left me feeling a bit iffy. I'm managing a bit longer with HL2 with each go though - wait until you get to the airboat and taking down the gunship that drops all the mines - that one section pulled me in like nothing else.
As for showing it to other people, try and show it off to a friend/relative/neighbour who has no idea what a Rift is and doesn't know about it until they put it on. I did that with my next door neighbour and it pretty much blew his mind. He had no idea that this tech existed, and it really was like showing off something magical. It's an amazing feeling to be able to do that for someone.