I was Thinking what i should buy and is worth it i mean i think both games are good but i just want to know which one is worth playing for months and not get bored of. I saw both of the gameplays but its hard to decide what to play.. Any Ideas?

There are many other games out there or coming out too try aswell but between your the two you listed go with wow.Ive played aion since day one and wow aswell and wow is just better no other way too say it.As for other games there is always everquest (doesn't have a huge amount of people) Guildwars(Guild wars two coming soon).Starwars the old republic(played in beta not as good as you would think but still a good game).There are many others but not going too go into listing them.