QtParted skills

Qtparted, the partition tool that comes with Knoppix had rubbed me the wrong way previously, by renaming the partitions and thus causing the system to become unbootable.
I had another opportunity to use Qtparted. This time I wanted to resize an NTFS partition to make way for a Linux distro. Before using Qtparted, I had defragmented the partition in XP. (which brings me to the question does Linux have such a tool?)
Then I booted with Knoppix, opened Qtparted, set a new size for the partition, and applied the changes. It must have taken less that 5 minutes for the job to complete. I was taken aback by the speed with which the partition had been resized, that I was quite sure that the data had been erased. But, that was not the case, I could see the files in the resized partition, as well as boot into the XP installation which that partition contained. The 1 hour defrag process in XP may have some say in Qtparted's quick response. Interestingly, it was an NTFS partition, a file system which cannot be written to in Linux (in my knowledge).

So, far so good.
But then the Linux installation started acting up, or rather the GRUB in it did. While the Opensuse installation went smoothly, after restart, GRUB would stop with an Error 18, before offering the boot menu. Thinking the Grub menu would need some tweaking, I tried booting with Knoppix. This time Knoppix did not boot, but stopped midway with some hard disk or partition error. Then I tried using the FC 8 live CD, and the Gparted partition tool in it showed that the resizing operation had left a 5 MB space free between the partitions. Could this be the cause of the error? I checked Grub's the menu.lst entries and found them to be valid. So probabably Qrparted's crude resizing had something to do with it.
The 5 MB space was the result of the unused space on the cylinder. Usually, when partitions are created, the sizes are rounded off to include the entire cylinder. So it is quite common to find paritions that are a few MBs off from the user's desired size. In QTparted, the partitioning does not do so, leaving the rest of the cylinder free. Since a new partition will start with a new cylinder, the free space remains free.
A Google search revealed that the Error 18 is a result of improper disk geometry reported by the BIOS to the OS. So the partition table was incorrectly written thanks to Qtparted. Some other sites also report that an EXT3 partition could also be to blame, since I had used EXT3 for the partition this needs to be checked.
The Qtparted problems also prevented rewriting the bootloader, which I tried to do with the Sabayon Live Cd. SAbayon offers installation option including a full install or upgrade or bootloader installation. Doing the latter produced another error. So I tried creating a new partition by deleting the earlier one, but this too ended in some hard disk error. After the aborted bootloader modification with Sabayon, Knoppix booted without problems. When I tried to use Qtparted to undo the damage, it would not cooperate. The options to delete or resize the partitions were greyed out. Even when the partitions were not mounted.

Update :
Plugging the hard disk onto another system seemed to solve the Error 18 problem, and the boot menu and all installations in it worked fine. This was strange. Then it struck me that the BIOS settings could be the cause for the change in behaviour. So I reinstalled the hard disk in the original system and changed the BIOS parameters for that hard disk to Auto, from the previous Manual (which can shave a few seconds off the booting time). Voila, the error 18 vanished.