Try the following.
Plugin the CD-Drive.
Turn your laptop on and imediatly start tapping the "F2" key and keep doing so untill you either get the error message about system disk, or untill you get the BIOS(setup) page. If F2 doesnt get you in try doing it again but tap the "DEL" key instead.
If neither of these work then...
Go to the following DELL website and enter your laptop's "Service Tag" number which should be on the bottom of your laptop. This will then take you to the downloads section for your specific dell laptop.
Once there look to see if you can download the "setup guide" or "user manual" for your model of laptop. If it is then download and look in it for the key to press to get into the BIOS.
http://support.dell.com/support/down...n&s=bsd&~ck=mn
Ok once in BIOS, look for something like "BOOT ORDER" then make sure that the "CD-ROM" is set a 1st boot, it doesn't matter what the rest are set as.
Insert the Windows 98 CD.
Save your BIOS settings then exit. The computer will then reboot and if all goes well you should then get prompted to "boot from CDROM" which you say yes to.