I have done between 10 & 20 SimplyMEPIS installs since I started using it last Oct. (2004). I don't recall ever seeing your error msg.
Did you follow mwallace's advice about deleting, repartitioning, & re-installing? It is very sound.
Your post is a little contradictory:
They are each over the 26 GB
Perhaps a listing of
(in a "code" block, please -- it preserves the column formatting) would be helpful.
I love the characterizations:
Lilo is quite vicious and ... the slightly-less-vicious Windows bootloader
Nice phrasing, motub.
However, given GRUB's greater flexibility & ease of administration, I would consider lilo a last resort.
I really think that
"Sorry, Installing GRUB failed.
New root filesystem may be faulty"
is saying that starting over is a good idea. Ergo, "follow mwallace's advice" above.