Cant enter BIOS or BOOT menu to format HD

I have a Packard bell easynote laptop I want to format the HD to change the oS from Vista basic to Windows 7. When I press F2 to enter BIOS or F8 to enter BOOT menu the computer continues to boot as normal Please Help as I need to get this ready for my daughters birthday

are u using a usb keyboard to connect to the laptop, if you have an older computer the bios might not support usb so it wont recognize it until you acutly get in to windows.
if you are try using the keypad on the laptop

No I am just using the combined keyboard on the laptop

Try the Delete (Del) or Escape (Esc) key on boot. See if that works.