Title says it all. Personally for me - Metal Gear Solid as series, story is amazing and everyone should give it at least a try, so many easter eggs, replayability, amazing characters. Sadly franchise has been killed, but games that have been released are still available. Would be happy to hear about others' opinion!
Saints Row (besides 4 because fuck that unrealistic bullshit, however it is a good open world mess around game)
Command & Conquer is my all-time favorite. The nostalgia I have from playing Red Alert 2 and Yuri's Revenge multiplayer as a kid is wonderful. I remember downloading custom maps with missing cameos for every modded unit and playing 1v7 AI games. Still do that today on occasion. The series has never had the most advanced games in the RTS genre but placed an emphasis on singleplayer, making it still fun to play way past the multiplayer's death. You can't forget the sprawling third party client communities and the vast field of mods that the loyal fans have made, however. Balance patches, content packs, unique maps, you name it. To be honest, the hate on EA seizing Westwood is not completely deserved. That doesn't mean that they can be forgiven, but most titles released past the Westwood phase are still solid. You have good games like Generals, CNC3, RA3, and Renegade. Generals Zero Hour is a classic, and I've recently gone back to RA3 Uprising just to beat the mini-campaigns because I never actually went through all of them. I also need to play Kane's Wrath at some point in the future. Of course, that's obviously skipping their canceled Generals 2 project (which was just called Command & Conquer), CNC4, and their shitty pay to win browser game. I could go on for hours about everything that CNC4 did badly, but I won't here. The series' 20th anniversary passed on August 31st, 2015, and there hasn't really been any news or upcoming releases for a while now. I'd like to blame that on EA recognizing that their newest additions to the series are awful but it's probably because the genre isn't as big as it used to be. Whatever game they would possibly release would probably be filled with microtransactions anyway. The most recent good thing that EA has done is bundle all the games in the franchise into one $19.99 item on Origin. Amazing buy, one of the best ways to spend 20 dollars in my opinion. Nevertheless, the legacy has already been made and the titles still stand today as some of the best of all time.
Warcraft 3, WoW. One of the best RPGs, one of the best MMORPGs, has known about this series for 10 years, and I don't regret that I learned about it
Mine has to be the littlebigplanet series. it isn't getting better as a series but the first one had the most charm and enchantment for me before and after teen years.
Seconding MGS, adore all the main series games. Big fan of Super Meat Boy as well, incredibly well made game that has insane amounts of content and knows what the hell it's doing. I remember playing the first years and years ago and thought it was fun. Had the second one at one point and wasn't a big fan. I'd like to replay those sometime, fun games but the floaty controls weren't my thing at all.
My favorite series of games is the trilogy Mass Effect. Incredibly global. One of the best games for the entire gaming industry, once critics put her the highest scores....
My favorite game so far is Nier:Automata It's one of the first JRPG/Hack n' Slash type of games that I've actually enjoyed playing. Difficult, but it has great storytelling, beautiful atmosphere and the side-quests are actually worth completing for once. I never came across an issue when it comes with porting but this mod made the game much more playable for me in terms of framerate. I'm like way below minimum requirements but I can still run it at a solid 45-60 fps without losing much quality. It's hard to say if it's worth $60, but what I can say is that it's definitely worth 30.
Medal of honor: Allied Assault, Spearhed & breakthrough! Just the best ever FPS game. Played it over 2000+ hours i think. They shutted down the servers 2 years ago. Very sad.
Kingdom Hearts franchise, despite how clubber fuck of a story it is. Also I've been trying to get into the Final Fantasy series, so far loving VI