Make sure when you exit the miner to press "Q" to shut down the process first. You'll know its safe to exit the miner program when the two cards say "DEAD" beside them. If you don't you will cause your display driver to crash, resulting in the experience you described.
It's hard to trust a site that doesn't spell-check or even just proofread their website. The english is horrid and they blatantly lie. The front page says "free unlimited disk space and bandwidth" but 1 page back they say "almost unlimited".
I've browsed around a bit and found campbx for exchanging my btc to usd and then transferring to my bank account. I was wondering if there are any better ones out there or if this one is reputable?
edit: please don't offer to personally exchange currencies for me. I am not so gullible.