Win98 MBR changed by W2k HELP!

I wanted to install Windows 2000 on my pc and when it wanted to re-boot I said ok. The problem is that my cd drive is not bootable so I declined the installation. Now each time I boot the machine I get that Windows multiple boot screen which shows windows 98 but the default is windows 2000.
Is there a way to get rid of this or even change the default to win98!
If I dont change it with the arrow keys and it counts down to zero then it tries to boot win 2000 and of course cannot.
H E L P please. Thank you.