As a gamer, I prefer to play Single-Player games that focus more on the story rather than the graphics or multiplayer. I basically like Stealth games but my absolute favorites are Adventure games & Interactive stories type of games and I am a HUGE fan of every single Telltale game (RIP Telltale). Actually, I don't care about Multiplayer games at all and I never play any except from HL2:DM which is the one and only exception to that rule, and even when I play HL2:DM, I'm never interested in a classic deathmatch or any other combat type of game. Instead I only enjoy jumping. This includes movement skills like bhop, strafe jump, surf & sometimes solving puzzles.
Recently, I've also started experimenting with some very interesting concepts in Garry's Mod. One night I joined a Star Wars RP server and I must say it was a very interesting experience.
UPDATE: As of February 2018, I started playing Counter-Strike: Global Offensive and I have to confess that I'm becoming increasingly addicted to it. This contradicts my previous statements but since I've been out of online gaming for such a big part of my life, I want to allow everyone to be able to see the whole story, so I'm leaving my previous text as is. This is something entirely new. OMG!

I am also a huge fan of any% speedrunning but I don't do any runs myself because I believe that this has to be a very serious commitment in order to make it count and I just haven't felt serious enough about this yet. I still really enjoy watching them though because sometimes they can be really impressive. There is definitely a lot of expertise and skill involved in a successful speedrun and I find it very interesting to watch what kind of result such a great amount of study, effort and skill can produce.