just joined the site, and thought that someone at some point might want the exacts on a few of the os's:
without office, the absolute minimum ratings for some of the windows versions are as follows. not sure if office adds some kind of necessary amount, though as mentioned here, bare minimums are not considered 'comfortable'.
hard drive space is also bare minimum - in some cases i have some data as to the full range of possibilities.
Win XP Pro: 233mhz, 64mb RAM, 2gb hard drive space
(the above applies to the corporate version, not clear if other versions of XP pro have a different ram requirement)
Win Me: 150mhz processor, 32mb Ram, 320-420mb hard drive space
- earlier versions (below) don't complain about mhz -
Win 2k server/adv. server: 256mb RAM, 1-2gb hard drive space
Win 2k pro: 64mb RAM, 650mb-2gb hard drive space
Win 98se: 16-24mb RAM, 195mb hard drive space
hope this helps