the thing is (i think) after you just added the boot manager it did change the order that w2k see your partiontion.... for example it was on drive d: and now it swith on drive c:.... the think you will have to do is to connect to your w2k from a another comptuter and run regedit and connect to the one that is having the prob. and find the key:hklm\system\mounteddevices you will find your assignation for your drive... and change it to what it was.... it should work...
(it did that to me just after ghosting it... and trying to boot with both drive...bad thing to do with win w2k...)
hope it did help...