My initial install of slack was on a 6Gb slave drive hanging off of my 40Gb Windows partition (back in the days when I knew very little about anything) and having another computer to back everything up on to now, I've finally gotten round to reformatting the Windows drive and installing Slack on it... I even removed the partitions from the linux drive to stop it from trying to load the old install's swap. But lo and behold, when I reboot, it gives me my OLD lilo, and then proceeds to tell me that it doesn't work...

But when I carried on trying to fix things, I put a Linux partition back on the 6Gig drive and the old linux install now boots... with no swap obviously, but this is a major pain in the ass... I think all I can say about all of this is... help! I don't really mind wiping both the drives and starting again, but I don't really know how to go about it. Preferably, I just want it to load up the newer version of lilo.

You should boot using a Slackware cd with the boot parameter pointing where your root partition is. When a Slack CD boots, it suggests this as indicated on this screenshot. Once you have booted to the right system, you should run 'liloconfig' as root in order to set it up correctly.

That did the trick... thanks!