Battlefield 2 vs Europa Universalis
Battlefield 2
Battlefield 2 is one of the Battlefield classics and rightly so. The game lets you play as a soldier in one of the three major military superpowers: the United States, the Chinese or the newly-formed Middle East Coalition. Players will have access to a wide range of weaponry to do battle with as well as a variety of vehicles. Similar to the original game, the game has a large-scale multiplayer mode - the hallmark of any game from the main Battlefield series - that can accomodate up to 64 players on a single map.With more weapons and vehicles for you to play with, Battlefield 2 is a pretty nice sequel to the Battlefield franchise. However, considering that it has not yet been reworked, unlike the first Battlefield, and that currently, there is no way you can purchase the game unless you get the hard copy off eBay or a similar site, you might be better off buying any of the other Battlefield games.
Europa Universalis
Europa Universalis is a historical real-time grand strategy game that includes all aspects of world history in the Early Modern Europe era, a period of time between the end of the Middle Ages and the beginning of the Industrial Revolution. Due to the game's meticulous need to be accurate in its historical accounts (period monarchs, known military leaders, and technological advancements), the game can, in some way, be doubled as an educational game since you can learn quite a lot simply by playing it.That said, the gameplay in Europa Universalis is just incredible for its time. The game is played on a huge world map that is divided into around 1,500 provinces where you can literally govern your nation the way you like. You can get involved in your nation's colonization efforts, explore new lands, trade with neighboring countries, wage war when they renegade on that very trade deal, spread the religion you've adopted far and wide, and of course, navigate the tricky political waters of diplomacy.
Not to mention, instead of using a turn-based format, the game has opted for a pauseable real-time format, so you can pause the game, issues orders and plan out strategies, before unpausing the game and let the world events play out. There are even tons of historically-based missions and events which may affect the world based on your actions and decisions.
When it comes to grand strategy games, there are only a handful that truly embodies the genre, and obviously, Europa Universalis is one of them. However, being the original game in the franchise, the graphics might be a bit worn for wear, but if you don't really mind, you can definitely pick this game up from GoG.com.