I've been dual-booting Ubuntu 12.10 and Windows 8 on my machine.

This morning I selected Ubuntu in GRUB, the menu disappeared and nothing happened.

So I thought I'd go into recovery mode and fix whatever was preventing the OS from booting. However, the boot just stops at "loading initial ramdisk" and sits there with a blinking underscore.

What confounds the mind is that, to my knowledge, I've done nothing that should affect the ability of the OS to boot. Everything worked perfectly last night. I haven't installed anything in weeks, I haven't messed with any drivers, and I haven't done anything particularly exotic while in Ubuntu. I pretty much exclusively use the OS to do assignments in a Data Structures course I'm taking, which really only involves creating and running .c files and extensive use of valgrind.

I'm pretty unfamiliar with GRUB, so if there's some sort of script or report I'm supposed to provide, then point it out and I'll be happy to get it.

Thanks in advance,
~Sam Flo