I LOVE the HL games... all of them!!
I'm not a huge gamer, so ive not played loads of other games, although ive played:
quake 3,
crysis 1+warhead,
Far cry (although i couldnt get past the helecopter bit without cheating, which then ruined the game)
Tried system shock 2, and deus ex, but couldnt get on with them (I admit i probably didnt give them enough time.
but for me, that only helps make the half life games better to play.
I dont have mad FPS Skills hehe, so i struggle with running around with rocket launchers shooting everything that moves type games, so Doom etc dont really do it for me (although i appreciate what they bring to the table).
I dont have a particularly good memory either, so any more than about 12 keys required to play the game, and i struggle to remember what key does what, looking it up every time ruins the flow of the game for me.
For me, The Half life games are the perfect mix... you can run in, machine gun blazing, or snipe from afar with the crossbow. I find the games are not too complicated in terms of control, and all this helps the story of the game come through un-interupted.
For a non Hardcore gamer here... Half-life is the best... in fact im itching for another run of halflife 1, come on Black Mesa... where are you???
I also need a new halflife to play, so come on valve!! sort it out!!