Well, I've been playing ArmA 2 since it was released and there's only been one MAJOR problem for me. Every once in a while (time in between can change) There's random shafts of color (usually black or white) that appear, and if I look in the direction they're in then my screen goes psycho. My friends have only had one or two instances of it, so I dunno if it's my computer, but it gets really annoying. And I know it's only with Chernarus and Utes, because I've tried both Sahranis, Porto, the PMC demo, and various other maps and absolutely nothing is wrong. I'll take a screenshot of it as soon as possible, but until then I hope someone knows what's happening.
Edit: Here's the screen glitch