Boot problem in two HardDisks.

I Have problem with H.D.D WDC with OS winme,the problem it could not boot as there is no H.D.D or OS when it’s master drive but the BIOS could veryfing it and there was an O.S on this drive. when i connected as slave the Bios verified it and diplayed it’s normal size properly as Slave with other good H.D.D the OS(s)(WinMe & Win98) did not also find it’s with the master H.D.D’s Drives in “My computer”…When i try to enter the fdisk option of the start-up disk options it did work.By the waytwo H.D.D.(WDC & Maxtor) have the same problem in the same day 27-Apr-2003 they are connected in LAN .How could i fix this problem? at least how could i recover H.D.Ds’ data couse it is so important to me..