Windows 7 installation keyboard and mouse disabled

I was having some problems with Windows 7 and decided to use the upgrade feature to reinstall it. I used the CD that came with my PC; a DELL Inspiron 580. The Upgrading Windows part worked fine, and I was told that the Setup is preparing your computer for first use. However the password screen did not appear (stage 16) and on the 'Set-up Windows' page (stage 17) I cannot click on any of the three options (see below) because my keyboard and mouse do not respond.



The keyboard and mouse are both plugged into a USB slot and I don't have any PS/2 slots on my PC. I have tried using all the USB slots on my PC but none of them work.

The keyboard and mouse work on BIOS but as soon as I go to the 'Set-up Windows' page they're both disabled (lights go out).

I've tried making an Windows 7 Home Professional 64 SP1 boot disk but this has not enabled me to use my mouse of keyboard.

I've checked my BIOS setup for the USB 3 and Legacy USB options but cannot see either. Though my version of BIOS (American Megatrends V02.67) looks old, so they may be called something else.

Please advise how I can select the options I need to select in order to finish reinstalling Win 7 onto my PC.