I have an old computer(Pentium 133) and I cannot boot from Win98 cdrom. It can boot from win2000 and xp CD. Win98 cdrom is confirmed bootable in other PC. BIOS set to CDROM first. What can be the problem? I also changed the CDROM drive
Sounds like you done everything necessary as you've already set your pc to boot from the cd rom and checked that the disk is indeed bootable. Perhaps try a floopy boot disk as already suggested by MAC101.