Okay, so I had a dual boot of Tango Studio (based on Ubuntu 10.04) and Windows XP.
Yesterday I downloaded the .iso for Ubuntu 11.10 and attempted to install from a USB (my BIOS won't normally boot from USB but I had PLOP boot manager on a CD). I booted up Ubuntu from the USB and then from there formatted the partition with Tango on and installed Ubuntu 11.10. On booting up I came into Grub rescue mode. So I booted up from the USB again and used boot-repair to reinstall Grub.
After this I would see the normal Grub menu, but on choosing Ubuntu I would come to a black screen. On choosing recovery mode it would begin starting normally with no obvious errors but instead of coming to a cli I would just get a blank screen with a flashing cursor on the top left, not accepting any input.
I have since reformatted and reinstalled from a CD rather than USB and had the exact same problem. I used boot-repair again and the result is the same. Output of the most recent boot-repair is at http://paste.ubuntu.com/869805/
I have also tried editing the ubuntu grub entry and replacing quiet with text nomodeset as I saw in an answer to another question. This got me a bit further - I saw the purple ubuntu loading screen but still came to a blank screen after that. Anyway, in most of the other questions in which that is brought up the user is still able to boot into recovery, while I am not.
Can anyone help? Thanks in advance, let me know if there's any more info I need to provide!
EDIT FOR MORE INFO:
I read something saying it's quiet splash that should be replaced with nomodeset. Earlier I had left splash in the line. So i tried it this way and it froze after displaying the following text:
fsck from util-linux 2.19.1
mountall: Plymouth command failed
mountall: Disconnected from Plymouth
/dev/sda5:clean, 139359/1741488 files, 745830/6961125 blocks
From a bit of googling it doesn't look like plymouth is essential, but I've checked and I do have the most current versions of mountall and plymouth installed so I don't know why there's a problem
EDIT FOR MORE INFO AGAIN:
I used dkpg --reconfigure plymouth cause I saw it mentioned in another forum and it still says plymouth command failed on boot