After actively using my computer pretty much all day so far, I just restarted, and it won't boot up past the XP splash screen. It won't boot in any mode, with any options. The blue screen prompt says "unmountable_boot_volume" and rather than diagnosing this myself on google, this seems like a pretty serious problem I'd like to get some actual feedback on. For some additional information, the computer is a Dell, less than 3 years old, and hasn't had any problems with BSoD in the past. Thanks in advance for replies.