Either one will work. I prefer OS X.

If you stay Windows, I'd recommend XP Pro over XP home.

If you go Mac, do NOT be among the first to get Tiger....similar thinking to not getting new cars their first years, except that OS issues are resolved much quicker.

If you go Mac Mini, buy some RAM from MacMall or OWC, install it yourself, and sell the "old" stick that came out of it after you've verified your system runs OK (you'll know in a couple of days' use).

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1990 190e 2.6 - The only one I can really call "My Car".

1987 190e 2.3 - The donor car's up and running, only mods are Euros and a Sony headunit. My Dad's runabout now.

1990 300e 2.6 - The parents' ride.