Firstly thanks for reading, I saved up and bought a new iMac 21.5" a month ago, with the wireless keyboard and magic mouse. Everything has been fine until today when i turned the computer on and there were problems when scrolling up and down the page on any application, it was almost as if the image was being distorted across the middle of the screen, a band about an inch in height. It was almost as if i was looking through a glass of water just at that part of the screen, and all the text was warping. (Not really dramatically, but certainly noticeable.) So i turned off the computer and left it for a while, and when i came back to turn it on it has an even worse problem. The scrolling and zooming (using clrl) is now incredibly jumpy and 'un-smooth' on all applications. (The best way to describe it is like a really smooth DVD tray open on a player, which all of a sudden starts jumping and jittering when you press eject one day.) I don't know much about computers, but it seems as if the machine can no longer handle the most basic of tasks, either that or the bluetooth is just not working properly, i think this may be a likely option as i have also noticed a lag/jumpyness with the keyboard. Safari and the other programs seem to be opening ok though. I have been downloading some HD films so it could be a virus, but i was under the impression these were very rare on Macs? I would attempt a system restore by date if it was my old PC, but there doesn't seem to be the option with the MacOS. Sorry i'm such a Mac newby, i've loved every minute of owning this machine so far, and this has really ruined my day. It's still under warranty obviously, but is there a more simple solution/set of tests i can do to find out what the problem is? Thanks so much to anyone who can help. Paul.