My old XP machine seems slow compared to my new machine. But let's begin.
Read http://forums.cnet.com/7723-6122_102-510824.html where we POP THE HOOD and figure out what's going on. This machine did not have a virus.
Read http://forums.cnet.com/7726-6132_102-5098912.html?tag=posts;msg5099421 where Grif tells us about second opinion scans.
XP does have some unfixed issues such as it's DMA issue, but your post omits make, model and details for me to comment further.
Bob
I already scanned the computer for a virus/trojan and it should be updated. However, when I load my computer, it is very slow. I open the task manager, and it has a bunch of processes. Some I'm sure I don't need but I'm not quite familiar with them yet. Could this be the act of a virus and/or Trojan? I have Microsoft Security Essentials for a antivirus program. The more these ******** do this, the more they will find themselves in trouble. Even after I end a process, it comes right back in the window. This is Windows XP Service Pack 3. I can reinstall Windows, but I'd hate to do that. It's also on a laptop. My firewall is working (that I know of).

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