Well, not every BIOS looks the same. First thing you need to do is understand what keys are used in the BIOS. I know when I view the options for boot order, I have to use the Page Up/Page Down keys.
There are usually several screens, so changing the boot order might require you to be on a screen other than the one that initially loads.
When you find the place to change the boot order, it might look like this: A, C, CDROM. You need to scroll through the different options until you get something like this: CDROM, C, A. Otherwise, your BIOS might give you options for first, second, and third boot device. That should be self explanatory.
After you've made your changes, be sure to choose the option to exit and save. If you exit without saving, then your changes won't matter.
I hope that helps and that you are able to get it working.