Before installing W2K I would check the HP homepage for BIOS model specific updates for your notebook because W2K is much more fussy than W98 about how and where it sets up.
If the notebook requires other files to run most likely these will be on your original CD (or preinstallation software) and thus will be part of the HP-W98 installation program making it difficult to extract them individually.
If the updated BIOS is not the issue, try re-installing the original pre-installed software and then do an upgrade install of W2K - not the best way perhaps but still better than W98.