firstly, when you try putting things on primary/slave, do you have your system disc on primary/master? Disks have jumpers on the back to tell it whether its a slave, master and sometimes whether its a single disk. Maybe your disk is set up as the latter and needs jumpering to primary/master before things are recognised on primary slave.
Spookily enough, last weekend nothing was recognised on my primary ide channel - - it turned out that the disk on primary/master had gone to meet its maker - still don't know why it didn't pick up the primary/slave - - probably confused you now ain't I ??