I installed 12.04 on my PC months ago alongside windows xp. Both are on separate drives. The PC loads ubuntu as default however recently it stopped recognising it as the default and now loads xp. I haven't changed any settings. If I unplug the drive with xp on, ubuntu loads up fine. I do need the xp from time to time for some of my work but I use Ubuntu the rest of the time as it's superior. The question is, how do I fix it so that ubuntu is default again. There doesn't seem to be any way within xp, not that I can find anyway. Regards
This is a BIOS settings problem. Boot into BIOS configuration page and change the order of the boot devices. Set the device (HDD) with Ubuntu first in boot order and your problem will be solved.
Another way (if you don't want or don't know to interfere with BIOS) is to run the boot-repair program. Look here for a How To