I'd be inclined to link to TrackMania Nations Forever. Arcade racer, Nations is free and contains a pile of content and a track editor. Of course, there's also United Forever, which contains about seven times as much content. And a puzzle mode.

Mine likes Age of Empires 2 and Rise of Nations... I think he is way past most of WoW's active players in play time. :)

My dad loves to read fantasy novels, so his game collection consisted of games like Quest for Glory, Riftwar series (Krondor), etc. I also remember he had War for Middle Earth since hes a Tolkien fan.

The best thing is find his interest and find a game that reflects that.

Yeee...es? ;-)

My dad always liked slow-paced games or sims - Panzer General 2, all Silent Hunters, Il-2, etc. I tried getting him hooked on newer Fallouts but unsuccessfully.

Then he saw me playing Mass Effect... oh boy.
He beated ME and ME2 multiple times (on Insanity D:) and now went back again to ME1 to complete Insanity runs with each class.

I'm scared XD

You don't know fear. My dads been playing Runescape for around 5 years now.
He uses other games as a holiday from it.

So... what sort of Shepard did he play? And which (fe)male did he nail?

hmmm let him play games with good stories. adventure games or rpg that aren't too difficult or tactical (he still needs to learn how to play games so nothing difficult or it may turn him off).

I distinctly remember my father getting for no apparent reason getting hooked out of nowhere on legend of zelda (first one) and I know there is a pc port so maybe try that too...