I'm not asking anyone to fix my computer. The tone of your reply makes it seem like you've given me all this valuable information that I've done nothing with, when in actuality, all you've given me is "It's either a hardware or software issue."
Also, downloading is not rocket science, if I say I can't get the trial to download, than I can't get it to download. I even made a new account and it wont work. My conclusion that the trial might have ended came from the sentence posted on the page before the download is supposed to start, which said "The 90-day Trial is offered for a limited time and in limited quantity. The download will be available through March 31, 2010, while supplies last."
So, to start over, the only "software" on this computer is Windows XP. So if it's a hardware issue, I just need to know what could be messing it up that would cause lag but not any system start up errors and what not. And if it's software, all that's on here is Windows, and it's the windows that came with the machine.