Where do I begin... I can hardly do anything on Ubuntu 12.04. I am very close to removing and returning to Windows. First I could not load it because the graphics appeared to be running low but somehow that stopped happening and I could log on. Now I can not download anything or I get this message

Cannot write: No space left on device.

I tried trouble shooting this issue but every time I try and fix the problem I am blocked by this message

E: Write error - write (28: No space left on device)
E: Can't mmap an empty file
E: Failed to truncate file - ftruncate (9: Bad file descriptor)
E: The package lists or status file could not be parsed or opened.
$ OLD=$(ls -tr /boot/vmlinuz-* | head -n -2 | cut -d- -f2- | awk '{print "linux-image-" $0}')

Ubuntu is also running incredibly slow and I cant get anything done! Please help this is driving me mad!