I've never had a laptop with the hidden partition, so take what I say with a grain of salt (I may be comletetly wrong).
It will depend on what you want from it. I think there was supposed to be same sort of application to guide you through the process of burning the contents of that partition to CD's or a DVD and a way to boot off it and restore the system ot the original cnfiguration from Toshiba.
If you just want to "see" what's on it and all, PartitionMagic has can hide and unhide partitions on hard drives. You should just be able to unhide it with that, then access the partition as if it were another drive on the computer. But if you do this, I don't know what will happen to your ability to do a recovery on the computer. So you've been warned.