i have windows 8 installed on my computer , when i press f12 for booting i get a option called select booting device ,
cdrom
usb fdd
usb zip
..... which should i select
hi,
try booting again but with out pressing F12 as you dont need to press this to boot into windows.
if you want a boot able USB you need to format it try this download http://rufus.akeo.ie/
hope this helped.