Valve had an odd situation where they had three products to push (HL2: Episode 2, Portal, and Team Fortress 2), but none had enough content to be considered a full fledged game. They could have released them all as budget titles, but with the lower limit of $40 on the 360, sales would have been dismal. So instead they packed them up, and shoved it Half-life 2 and HL2: Episode 1 to form this big box of citrus gaming.
While we're talking about very different products, they all share the same customizable controls, save anywhere options (save for TF2), and the best achievement system ever seen in a 360 game. Not only can you easily track your achievements from the game menu, incremental progress is also tagged, so you can know just how far along you are for that "find all the lambdas" goal. The only minor problem is the loading going from the main menu to a game's sub-menu, which like the in-game loading, feels un-optimized after the seamlessness of the Halo series.
Team Fortress 2 has been ten years in the making, and all that time has resulted in the most polished game I have ever experienced.
Half-life 2 is a game you've probably already played, but it controls fairly well here (the vehicle controls are a little iffy), and is still a pretty great game that has an awful habit of repeating the same idea far too many times, like the vehicle sections that are about five times longer than they really should be. Artificial barriers in the levels and a story that seems to vanish at points are hard to accept after more polished experiences, but overall it's still a good ride with visuals that hover somewhere between Xbox and Xbox 360, with the fantastic surroundings suffering from low poly character models, though you'd be hard pressed to find a game with better facial animation.
HL2: Episode 1 is visually about the same, but thanks to its shorter length, the game is more tightly focused and more closely tied to a compelling story. This is aided by the near constant presence of Alyx, making small talk as she helps guide you on your way, and also covers your ass in trouble spots. Having her take the scope of a sniper rifle as you clear the way has to be one of the most memorable sequences of the entire series. Like it's predecessor, it also suffers from driving a good idea into the ground. Covering an ant lion nest with a car was pretty keen the first time, but after doing it over for the ninth time it was definitely growing a little stale.
HL2: Episode 2 continues the story and basic feel of the series with a minor bump in visuals and a stronger emphasis on heavy gunplay. It hovers between repeating all the ideas that have appeared in Half-life 2 before, from building bridges with the gravity gun to incredibly slow moving elevators, to some of the best set pieces the series has ever seen. The areas vary from the same leading by the nose as the rest of the series to wide open vistas, and the end battle needs to be seen to be believed. Story wise, it still leaves you wanting for the promised conclusion of Episode 3.