Boot hangs on blinking cursor from CD or otherwise

So I've installed Ubuntu 11.10 amd64 alongside Windows 7 on an Asus laptop with a corei7 processor and it's started hanging anytime I try to boot Ubuntu. It loaded initially, and did the initial install, but after booting into WIndows once, it seems unable to do anything, I'm left with a blank screen and blinking cursor in the top left immediately after GRUB in either normal boot or safe mode. Further, any time I try to boot from a CD or USB, I get the install menu, but once I select an install option I get nothing but the blinking cursor again.

I've got not USB devices connected (just the power and ethernet). I've tried deleting the quiet splash bit of instruction, but got a little nervous about adding/deleting any other things in there, being unsure of exactly what it is they do. I've also tried an install of Xubuntu 11.10 with the same result.