can anyone help me? my mom called me and said theat her computer all of sudden isn't working, i told her to unplug it and the replug it in and see what happens. She tried and nothing happened. she said when it comes on it says something about windows not being able to start up properly, the it goes to a command screen. does anyone know what this means? did she lose everything? is this going to be expensive to fix?

not really, her windows start up files are corrupted, get a windows xp cd installation, boot from that, go to recovery console...
type FIXBOOT
type FIXMBR