Ubuntu headache... any advise please

[kapslock]

Hi all, i am a complete Linux noob, and would really appreciate some advise. I am trying to install Ubuntu to a external usb hard drive, just to take a look at it and try it out. I have no problem setting the drive to boot first, or to format and install. It just will not boot to it, even when the bios has the drive set to boot first. I have unpluged my internal drives as i dont want to mess up my usual os and i am not interested in multibooting. I just want to boot Ubuntu from my external drive, use it, turn it off, reboot into my usual os. On boot, after install, grub starts to load then stops with an error similar to "killed innit". Any help much appreciated.
Many thanks

[dylunio]

Can you post the exact error you get please,

Also on which drive did you install grub? the MBR or the usb hard drive or the MBR of the internal drive?

MBR = Master Boot Record

regards,

dylunio