My favorite games of all time are a bit odd, given the kind of games that I make. I like a _lot_ of varied games, and there's a huge list of games that I really love extremely dearly. And then a mass of games I couldn't care less about.
Anyway, my absolute top favorite games are tied between Final Fantasy 6 and Chrono Trigger. Silent Hill 2 is maybe my third favorite game, certainly atmospherically. I'm a huge fan of a ton of the NES-era games and SNES-era titles. All of the Mario games from that time period, Marios 2 and 3 in particular. And really, all Mario games in general (the platformer kinds), all Mario Kart games, and all Zelda games. I even really like Zelda II, unlike most people.
I also have quite a soft spot for Castlevania II on the NES (I know, I know), Ironsword (even worse, I know), Chip 'n Dale Rescue Rangers, Rampart... and I know I'm forgetting many others. I liked FF4 pretty well, I grew up on FF1 and loved that, and most of the other FFs I'm just kind of "friends" with.
Secret of Mana was huge for me, Secret of Evermore was just a friend. Earthbound I discovered later, but really like.
My first RTS was Warcraft 1, and then Warcraft II was something I obsessed over. Age of Empires and AOE2 were then on a whole other level, and I really loved Empire Earth also. And I loved Rise of Nations. And then much later, Supreme Commander 1. I played the original Civilization a fair bit, but was never that hooked on it. Civ 4 and later Civ 5 hooked me, but less so in multiplayer.
I really love the tactile nature of a ton of shooters. Far Cry 1 and 2, Half Life 2 (and to some extent 1), and others I can't think of. When I was younger I did play Wolfenstein and Duke Nukem 3D and Rise of the Triad, but Quake 2 was what really got me into the genre. And then the Unreal Tournament games after that sealed the deal for me even more. Out of recent(ish) shooters, I really love Red Faction: Guerrilla, which I'm glad to finally have on PC and not just PS3.
There were some Atari 2600 games that were really formative for me, although I wouldn't call any of them favorites. Some other early PC games in that group, too. I also really like board and card games. I was huge into Magic: The Gathering for years as a kid. Basically Revised through... maybe 6th Edition? I still have maybe 5000 cards in my closet, waiting for my son to be old enough for me to inflict them on him.
SimCity 2000 was never an absolute favorite
game of mine, per se, but it sure was a staple of play. Forgotten Realms: Unlimited Adventures was a favorite of mine in middle school. I loved creating adventures with it, as you might imagine. Demon Stalkers, from the late 80s, was another favorite PC game of mine. I also really loved Lode Runner: The Legend Returns on the Mac, and only later had it on the PC. Demon Stalkers I used the level editor for extensively, as with FRUA, but I didn't much with LR:TLR.
Oh, that reminds me of Maniac Mansion for some reason. That on the NES was one of my favorites also. Day of the Tentacle on the PC was also pretty good, but lost a lot of the magic for me. In recent years I've been big into Minecraft, and Left 4 Dead 1 and 2, but now those have both been supplanted by 7 Days to Die. Back in the day I was really into Descent 1 and 2, and Descent: Freespace, but now I think that Strike Suit Zero is starting to scratch that itch. In recent years I've also been really taken with Rebuild 2, although Rebuild 3 has yet to grab me in the same way.
I have a long list of other games in my backlog to play, and I've played a ton of other games that I really liked, loved, or was anything from meh to hating on, but that's already a way-too-long list.
I have a really wide taste in genres, and I don't tend to have much loyalty to a specific platform -- it's all about the games for me. Though lately (past 5ish years) pretty much everything is either Nintendo or else on the PC. A Link Between Worlds is the best Zelda game in a couple of decades, I'd venture to say, incidentally.
Okay, that's enough.
Happy New Year, by the way, everyone!