Virus on Computer - Unable to Get Rid of Help.

[COLOR="DarkOrchid"Tech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft Windows XP Professional, Service Pack 3, 32 bit
Processor: Intel(R) Pentium(R) M processor 1.86GHz, x86 Family 6 Model 13 Stepping 8
Processor Count: 1
RAM: 1015 Mb
Graphics Card: Mobile Intel(R) 915GM/GMS,910GML Express Chipset Family, 128 Mb
Hard Drives: C: Total - 57223 MB, Free - 4922 MB;
Motherboard: Dell Inc.,
Antivirus: Microsoft Security Essentials, Updated: Yes, On-Demand Scanner: Enabled]I have been unable to get of a virus for the past couple of days. AT first I had a problem with the icons changing, then there was the problem of the monitor blacking out, now my cd rom doesn't show up. I have installed and uninstalled different av software, Kaspersky, Trend Micro and now Microsoft Essentials.

Any help you can provide is appreciated[/COLOR]