[Anthonycc]

It depends on what your style of play is, and which features you want. http://www.guildwarsguru.com/content/for-the-new-player-on-a-budget-which-guild-wars-should-you-buy-id2249.php gives a quite detailed description of what games to buy, and about halfway down the page there's a very useful little chart. I would personally start with Factions, because not only does it come with Assassins and a cool continent, but Factions content is pretty much a requirement for effective PvP. Plus Factions is the only one that gives you access to Alliance Battles, which are very addictive and fun.If you're more into PvE I would buy Nightfall, because it has a solid storyline, Dervishes, and micro-managed henchmen called Heroes that are extremely useful in just about any area of play. Nightfall also includes the Heroes Arena for PvP.Prophesies also has some pretty good PvE, simpler gameplay, and (unlike the other two chapters) you can get most of your skills for free by questing rather than having to buy them (which gets horrendously expensive later on).Hope that helped. Have fun playing :)