Linkage

I love the X-Com series. I bought X-Com UFO Defence (or 'UFO: Enemy Unknown' as it was in the UK) about 8 years ago and although I was pretty bad at it I still really enjoyed it. It was my first run in with a 'scary'/tense game, and it was cool because it had aliens and cool laser guns and stuff in as well.
After Enemy Unknown, the UFO series expanded in some fantastic and some totally misguided directions - Terror from the Deep is similar to UFO Defence but underwater, and Enforcer is... not.
But anyways, it's a fantastic chance to play the squad-based games as they were originally intended, and at around £8 (inc tax) how can you say no?

P.S. I also own the entire newer UFO series. Can anyone explain to me how to get the first 2 (Aftermath and Aftershock) to get a decent frame rate on modern computers? Maybe I should install Win98 in a VM or something.