Computer Problems

Argh, my computer is acting up again. Its been doing this for the past three days. In the beginning, everything is fine, after maybe an hour or so, the screen suddenly flickers and my start button and the bar disappears for about a minute. Then it reappears and all my windows are scrambled in different order. So everything is fine again, after another hour, the same thing happens except this time, the start button and the bar don't appear again and all of my desktop icons have disappeared too. The msn window that pops up when someone on my contact list signs in or I get a new email pops up in the upper left hand corner of the screen instead. The next day, when I turn on my computer, everything is fine again. I think I have some virus or spyware on my computer. Sometimes I really hate technology. Actually, its a bit more of a love/hate relationship between me and my computer. When everything works fine, I love it to bits, when it messes up on me like right now, I want to throw a brick at the monitor even though I know the hard drive is the one really at fault.