Hi praph_wicked, normal order would be, floppy drive first, CDROM second & Primary hard disk drive third.
How ever if your bios does not comply you can always press the F8 key every two seconds & that should bring up (Please select boot device). Which will look like this;
Choose the CDROM drive with the windows CD in it.
If you have just one CDROM drive, make sure the jumper on the back side of the CDROM is set to "Master". If you have two CDROM drives connected, set one as master & the other to slave.
If using an IDE cable for the two CDROM drives. The CDROM at the end of the data connector is to be set as master, the 2nd CDROM connects to the next IDE connector & Its jumper is set to slave.
Good luck!
Mike