...and Don't Panic
I'm still working my way through the hitchhiker novels (i think I'm on the fourth book in the trilogy), but I love them. I also have the british miniseries, which is pretty low budget, but still pretty great and I've watched it several times. I'd love to get ahold of the old radio show too, so if anyone has a link, please post it.
There's a fine line between fantasy and sci fi, but most people I've met who are fans are fans of both. I personally loved fantasy books when I was a kid, but only got into sci fi in my mid twenties (bout 12 years ago now). I really do prefer works like those of Arthur C. Clarke, where the extrapolations of science take centre stage, rather than the characters, but I guess that's what they call "hard sf". I think it was bassybill who mentioned above that he tends to think of fantasy more swords and sorcery type stuff and I kind of think along the same lines. I tend to think of anything that involves space travel, aliens, or time travel as sci fi. Ultimately, it's just semantics/classification systems though, and I'm generally happy to nerd out on either genre.