Lists of favourite games... aaargh, this is just as bad as lists of favourite books...
but it's fun looking at other people's lists, there are some really interesting games there that I now want to play, haha.
Currently my favourite game is The Witcher, simply because I'm playing it and enjoying it like I don't think I've ever enjoyed a fantasy RPG before. Maybe it's because it's the first time I've played a fantasy RPG set in a quasi-European setting that's actually made by Europeans rather than Americans. It... makes a difference. Also, I have the option of playing it as English game, English subtitles, and whatever I like audio (currently set on German). This I like, very much (several English accents irk me, and I can't distinguish accents in German yet, so problem solved! Plus I get German practice.). Also, it feels like whoever made the game really truly loved it - there are so many little details in characters, environments, everything, really. I can't wait to finish it and get onto the second game.
I also really enjoyed LEGO: Lord of the Rings. First time I've ever seen a LEGO game look so beautiful, and so many easter eggs that hint at pop LotR culture, haha. Plus, LEGO open world. Really cool. I enjoy LEGO games in general, but that one was really really nice.
Oh, an oldie that I still like to replay every now and then: LEGO Island. This is where my love of LEGO games came from. Absolutely ridiculous humour. The boss fight is chucking pizzas from a helicopter at the villain.
For something non-PC... Professor Layton. I love this series to bits. I've played them so often I can finish all in-game puzzles in the first game in 6 hours. First time I played Unwound Future I finished all in-game puzzles in just over 12 hours. The only game I'm missing from the series is the crossover with Ace Attorney, Professor Layton vs. Phoenix Wright. Whacky and heart-tugging storylines, coin hunts (this is also why I like LEGO games, pfft), really whacky characters and character designs and environmental designs (I wonder how the buildings stayed up, haha), and puzzles. I may be weird, but I really like puzzles. They're fun. And this series was really good, and improved on the same working formula for each game. A bit like what Pokémon do.
It's not really in my top favourites, but hey... Age of Mythology. Spent many hours playing through the campaigns over and over again. I mention it simply because FLYING PURPLE HIPPOS. Like all "Age of" games, the cheats you can get in this game are things of wonder.
Another long-time favourite... Return to Castle Wolvenstein. This thing turned into a family tradition, haha. Every year or so my dad and I will replay it, just because. I would be crazy happy if one day it receives a remake, but hey, we all know how likely it is that will happen.
I'll stop now. Whoops, I wrote a lot... *sheepish expression*