I suppose I have a duty to try to give you some solutions!
Anyway, first of all, defrag the hard disk and each partition thereon.
Then, run checkdisk to ensure there are no errors.
Do you have a partition formatted for Linux?
Boot with the Suse disk and choose to install - it will (should) resize the partitions. If not, then I am not sure why.
I don't remember any options for a custom install but I would imagine that they are there.