If I remember, you can flash the d220/230 models a couple of ways: within Windows, and via a boot floppy and/or memory stick. Have you tried either of the latter two options?
Does this model support the "failsafe boot block"? If so, the computer will still have the ability to boot from what they used to call the "ROMpaq diskette". You'll need to create one of these. You can also force a failsafe boot mode on some machines by holding down "esc" while powering on. Google will point you the right way, I expect.