Got it working somehow. Discovered that CD2 in the set was bootable. Booted off it then it asked for 'module disk 4' so I stuck CD1 in. Started up YaST and it found the packages ok! Started the installation, got through CD1 then failed halfway throudh CD2 due to an invalid package (susehelp-2004.04.05-2.noarch.rpm. Am looking on the forums for help with this.
Will look at the bios anyway. Thanks for all your help