In desperate need of help!

I’ve got a pretty big problem with my computer right now. I was testing out some old hard disks at home and then i found out that one of the is my sisters old drive, with xp and all her old files on it. So, i thought that i shouldn’t re-format and so. I unplug the hard drive and everything seems fine. But when i try to boot my computer it automatically boots my sisters old drive (NOT plugged into my computer at all) and got an error message. But i thought to myself that there has to be a dual boot that was created ubt it just flashed the options for half a seconds. so i got hold of a ps/2 keyboard (a one you type with). and when the computer booted i pressed the down arrow like an idiot and i was able to pick my installation, since when you press a key the screen stays. I wouldn’t have cared if it tried to boot my drive first or so, but it is really annoying. I tried ‘FIXMBR’ and ‘FIXBOOT’ from the windows restoration console but nothing.

So please help me if you can!

So, i thought that i shouldn’t re-format and so. I unplug the hard drive and everything seems fine. But when i try to boot my computer it automatically boots my sisters old drive (NOT plugged into my computer at all) and got an error message.
how can a computer boot a hard drive that isn’t plugged in?

if i understand you right, your sister’s hard drive isn’t connected to your pc, but your pc is trying to find it and boot from it, ignoring your own hard drive in the process. if so this sounds like the bios is looking for the wrong drive and you need to change your bios.

Good guess hyperfocus and thanks for the quick reply. I edited the boot.ini and everything is fine now. Sorry for the desperate post.
TO EVERYONE: Learn from this! If your boot record is trying to boot a non-existant drive, consult boot.ini. How to find Boot.ini (Windows XP Pro): Start Menu->Run->sysdm.cpl->Advanced-> Boot and recovery->Settings->Edit.
Always back up your Boot.ini!!! when clicked editing first of all, press save as to the desktop or wherever you like it.

Well, there a story with a happy ending!

you can also get to it a faster way

START>RUN “msconfig”