Inspiron 6000 performing slowly after system reinstallation. PLEASE HELP?

I recently reinstalled Windows XP on my Dell Inspiron 6000 laptop and now my computer's frame rate is exceedingly choppy. I should say that I haven't been able to reinstall all of the devices that came on my Dell disk. I'm trying to install the video graphics thing (which I believe to be crucial to solving my problem) but every time I try I get a message that says something like "one or more files are missing or corrupt" and then the setup exits with absolutely no elucidation as to what those files might be. Can anyone help me?