I'll agree with the folks saying Unity. Even if you've forgotten most of your co-sci learning, you should be able to pick C# up pretty quickly. The fact that you can compile for pretty much any desired platform, and it's free for the basic usage, and it does both 2D and 3D make it a really good choice since you aren't limited in those ways.
Alternatively, you could try Gamesalad. It's all drag-and-drop object "coding" and you can whip simple games out incredibly quickly. It's also free for basic usage, and compiles to a lot of different platforms. Really, if you want to start making a game and have something basic in a couple of days, Gamesalad is where you might want to start. There was a game jam a while back where some group's coders dropped out 6 hours in or something. The rest of the team grabbed Gamesalad and had a respectable game done 40 or so hours later when the jam was over. It's super easy to understand and use. The downside is that you won't really learn anything that could translate to another development platform, though.