My Desktop Looks Strange

Hello. I am using Kali Linux 1.03 i386 on a live usb (Sandisk Cruzer 16 GB) with persistence. For the first few boots all was well, but now the screen looks a bit like windows 98. and also when booting and mounting persistence my computer just freezes mid boot. To try and explain, I select live boot and add persistence to the end, and it loads what i believe are the devices. and then the screen goes black and more text appears, but sometimes it just goes black with a little bit more background light than the other time and stays there. Sorry if i did not explain it well enough. If further details are needed tell me and i will post them. Screenshot: http://i.imgur.com/Y62UExJ.png. Thank you in advance for any help.