Well, the recovery partition probably cotains not only the o/s but the drivers and apps that came with the system. You can always back those up and then just wipe everything clean. As far as hard disk drivers, you're probably talking about MBD chipset drivers (IDE interface and what-not), however if you have a OLD hard drive, and I mean real old, they used to contain HDD info on special partitions on the HDD itself (modern HDD keep them in its own internal chipset). You can't really delete those, though, with fdisk because it wont be listed, or if it is would be listed as unknown and would not remove it. The only way to remove this partition is by writing zeros, but I wouldn't recommend that if you have a old drive unless you know the info to enter into the bios (tracks, clusters, etc).