[xubuntu] I can't load into xubuntu?!

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http://ubuntuforums.org – I got windows xp and xubuntu 12.10, which are installed alongside on the harddrive and it uses the usual boot manager (GRUB) so I can choose which one to use. Then, I ran out of space disk in xubuntu and I believe that I literally have zero space. but after turning on computer again, xubuntu could not load and it gave a black screen saying 'checking battery state' and it lasted like forever. Now I got stuck and I have no idea how to fix the problem. But i can still access windows xp though. (Hardware)