Status: 0xc0000225 Info: The boot selection failed because a REQUIRED device is Inaccessible.

I have a HP TouchSmart 300.

When I try to turn on my computer it crashes at the loading screen. It only started today morning (27/12/2012). It also tells me to try and use the Installation disc, but every time I use the Installation Disk it loads the information but re-starts at the loading screen again! Is there any other way I can fix my computer?

Also when I try to safe mode (all 3 safe modes) It stops at the same file every time and to re-start it I have to turn the whole computer off.

I've also SET the Bios on CD and ROM loading.

Please can someone help?

http://imageshack.us/photo/my-images/837/img1144jr.jpg/

Kind regards WillI had problems similar to this on a laptop about a MONTH ago. Same status and everything but after i repaired windows it would say starting windows then bluescreen.  The recovery partition became unusable. So i had to back up the files and reinstall everything.  Before i reinstalled windows i scanned for malware with HIREN's boot cd with all the antiviruses available on minixp mode.  It found a few viruses and removed them but it was to late... I sugjest that you scan for viruses with hiren's boot cd.  I hope your system is not to FAR gone.What is new or different since the last time everything worked properly (ie, new hw, new sw, virus, error, etc)?