I have a computer with 2 Gb RAM. One of the the 1gb sticks went bad, so I replaced it. I ran multiple cleaning aps to clean computer of malware/viruses. BUt the computer still has windos that will open then go white and unresponsive and sometimes I cannot close them. Sometimes if I hit the start button and the window opens for all programs, then it will go white and stay there until I shut the computer down (via power button). When this happens I can still open other things like browser windows and they will work fine. I also deleted all browsing history. Any ideas?