LG monitor won't display anything via VGA cable

After updating to Quicktime 7.5 my screen on my LG lcd monitor starting moving up and down when using my mouse. After fiddling with the display controls to lock it back down it no longer displays anything through the VGA cable connected via the DVI adaptor to the monitor.
I am using a borrowed DVI cable to use the monitor, but I have to return that tomorrow. Tried permissions without any luck. Is there any fix for this problem so I can reuse the VGA cable without having to buy a DVI cable. Also, is there any solution to the floating screen problem?