Thanks for the replies guys. I have finally figured it all out. I now have XBMC (with EvoX as an app) as my main dash loaded using UXE. I have also successfully upgraded the HDD to a 200GB with F and G partitions formatted and working 100%.
I personally have no interest in XBL and have removed the msdash completely (still backuped of course). I have also installed a backdoor into the system with a SplinterCell gamesave exploit that loads to EvoX just in case.
I know this is the EvoX forum and I did originally intend to go with EvoX, but I primarily want a media center so I am using XBMC as my main dash. So once again, thanks for the replies and thanks for the community in general, I could never have done it without this place.