Set up Mini for new-to-Mac user

Instal Perian.
Instal Handbrake.
Instal Mac the Ripper.
Instal VLC!
Instal Permanent Eraser - unless Apple have sorted out the secure deleting issues. Having said that, this one is probably a bridge to far.
Instal Firefox (or chrome) with add ons like adblock plus, no script, download helper.
Turn on the Firewall - then make sure you don't get the iTunes glitch (that is so annoying, thanks for not sorting that years old bug out Apple!).
Sort out some of the folder order view options, including desktop, so that when you first throw a bunch of files in it doesn't look like your cat threw up on the carpet (LOL Apple).
In Safari, tweak the settings like turning off the 'open safe files' option.
Tweak the size and location of the finder window - who likes that in the middle? Also the default target file (mine is desktop) and then add the extra sidebar links to movies pictures, oh yeah add the download folder to the sidebar too.
Put disk utility and activity monitor as buttons at the top of the finder window - if they are confident enough to repair permissions or format stuff its handy having stuff near enough to hand.
I just had to do a load of this for some users that aren't that great on OSX and it is surprising how much easier this makes things.