Can't boot to hard drive after partitioning

Recently I used the Quarterdeck product PARTITION-IT to resize some of the DOS partitions on the hard disk of my computer (Pentium 100). In the process I moved (but not resized) the Linux active partition and the Linux swap partition. Subsequently the LILO boot loader went into panic mode.

I was able to use the Slackware boot/root floppies to mount the active partition (hda3) and it seems intact. Therefore I concluded that I would have to reinstall LILO from the hard disk, which I was able to do with the command

      lilo -r /mnt

which changes root to /mnt (where I had mounted /dev/hda3)
prior to installing LILO. This seemed to work, however I still get kernel panic when I try to boot from the hard disk.

Someone has suggested that I should use Linux <fdisk> to
reset the Linux partitions, however I understand this is a data-destructive process, to be used as a last resort only.

Can someone advise me how to retrieve the situation? More generally, what are the do's and don'ts of trying to use a DOS-based partition utility when Linux partitions are present? I should mention that LILO is using the MBR to boot to Linux/DOS,

Thanks for any help you can provide....

Roger Young,
roger@maths.grace.cri.nz