Vostro 3450 - change Boot

Hello,

I have Vostro 3450 with Win7.   BIOS - A13 version.

I can't change/chose option to boot LiveCD

In BIOS-> Boot Menu I have some position eg. CD/DVD, Hard Disk, eSata, USB, Network etc.

There is "!" sign before almost all cases - only before Hard Disk there is no "!".

I can change order. In BIOS Help is information about that I can use keys combination "Shift+1" - but nothing change.

When I press F12 when Vostro starting - there is: Hard Disk, Setup and Repair