Of course Slashdotters will tell you Ubuntu just like they want you to encode your music in ogg, but the answer is XP, clearly. It's still the standard, for better and (mostly) worse, so if the machine can run it, run it. If it's a donated machine, there are low/no expectations for future support other than scrub-and-reinstall, so XP makes the most sense. But also, what they said re: what's the machine's target use, maybe Ubuntu is a good route... but XP is unfortunately the best bet.
Somebody needs to tell them that the person on the other end can't appreciate their grinning and nodding.
Those pleated pants do go nicely with the headset, though-- nice look, bluetard.
A film camera shooting at 24fps typically has an exposure of 1/48 of a second. The other 1/48 of a second is used to move the exposed bit of film out of the way and to position the next bit of film in the gate for exposure. This is referred to at a 180-degree shutter, since the shutter is open for 1/2 of the 360 degrees of the camera movement's rotation. When the film is shot overcranked-- at 48fps or 72fps or whatever for a slo-mo effect-- the shutter is still usually 180 degrees, so the motion blur looks about the same when played back at 24fps.
Your test doesn't indicate as much about frame rate as it points to flaws in your rendering technique.
With accurate motion blur, your viewers would have a very hard time telling the difference between 24fps, 30fps, and 60fps.
Anyway, with Linuxes getting better and easier to run every day, more data and apps in the cloud and Apple leading the usability charge, let's hope Windows continues its agonizing death spiral.