The jumpers are the little black (usually black) plastic clips that sit over two of a number of pins at the rear of the drive - next to the power supply input.
Both drives should have a sticker on them that indicates the jumper positions. The jumpers short out connections that tells the drive what the configuration should be.
Set the jumpers of one drive to the master position, set the jumpers on the other drive to slave position. Connect master and slave to the one cable from IDE socket 1 and boot up. If it does not work, swap the disk positions on the cable (different mobos have different requirements as to HDD position)
Once you are in you should be able to copy the bits you need to the drive you are keeping,