I used to have a P4 HT that would boot win XP in 21-34 seconds, my 6 core 8GB ram Ubuntu 11.10 box starts up in about 5-8 minutes, but 4 of that is POST time, as my MB has 3 RAID controllers in/on it and 9 HDDs it takes a while.

I used to run Slax on a dual core celeron 1.2GHz 1GB ram laptop and it would boot in 8 seconds or less every time, from a 2GB USB stick

Puppy linux on the same laptop would take 12-17 seconds

windows 7 on my 6 core "Might" be booted and "usable" in 7-10 minutes, depends on if it crashes while loading the wrong driver for my 6GB/s SATA III controller that it refuses to accept the correct drivers for.