Bioshock is the perfect game in every way. The gameplay is smooth, the ambience is outstanding, and the story is absolute perfection. I remember playing this for the first time in the ancient days of 2007. The first time playing this game gives you a sort of high that you likely will not feel again unless you play Bioshock 2, which is also an amazing game in and of itself. If you haven't played this game, buy it and play it as soon as you're able. If you have, and you don't own it on GOG, buy it again and play it again. You know you want to.
This game dominated my childhood when it came to computer games. I never played Age of Empires, so I didn't have the experience with them to help me out. However, the learning curve in this game is almost non-existant. It's super easy to figure out how things work, with the only thing you really need to focus on is how to not blow through all of your supplies all at once. 100% give this game a go if you like RTS/Lite City Builder gameplay!
Fallout London is an amazing expansion into the Fallout Universe. The voice acting is top notch despite some hiccups here and there, and the story is fairly solid for it being a Fallout story. I mean, Fallout 3 and 4 are the same story but roles are swapped, so anything that isn't that is great. Some performance issues here and there, but nothing totally horrible. I think I only crashed a couple times, but definitely give this a try! It's free!