After running a malware scan (using MBAM), Windows' Automatic Updates told me I needed to reboot my computer, which is nothing new because it tells me to do so periodically.
When rebooting, it got past my computer's startup screen and then when it got to the Windows XP splash screen, it immediately went back to the startup screen and asked me if how I wanted to start my computer (normally, last configuration, etc.) I tried normally and last configuration but they just ended up showing the Windows splash screen very briefly and then doing this routine over and over again.
About two days ago, I scanned my computer with MBAM and it picked up something called 'trojan.vundo' which I think was causing the occassional popups on my computer, and yesterday it picked up four trojans, but MBAM said it quarantined all of these trojans. Could they be contributing to my problem?
Thanks so much for the help!