Some computer games are just a waste of time. However other computer games are very useful to you. They will train your mind like nothing else in the world, plus they will teach you a lot of things that most people never dreamt of before!
Let's start with the strategy games. These kind of games require a lot of inteligence and ability to learn. How many times you for example wanted to beat this or that kingdom and you couldn't before because you were not smart enough? Well, after trying and training a lot, soon or later you can be sure you will make it! Not only it will help you in the game because you brain is much more developed, but also it will help you in the world outside the computers, because like physical exercise it stays here for quite a long time!
Which games are very good for you? Let's start with kind of games: Racing games, strategy games, RPG games. These are the three best ones. The racing games will sharpen your reflexes and fast thinking like nothing else will do, the strategy game like I told before will ask your brain to release a lot of power that you never dreamt of before and the RPG will take the best of the two worlds, however the effects are not as powerful as the ones with the racing and the strategy games...
Now which games should you play? The RPG ones you should play include Pokemon Blue, Silver, Stadium 1 not the stupid stadium 2, all the final fantasy series specially the 8 and the 10. The nine is not a good one I can tell you. Learn how to master these games and not only you will have a lot of fun in the processm you will become visibly smarter! After all it's a great exercise for your brain in all aspects!
Most of these games are not enough to beat them, you need to do something even better than that, you need to replay them endless times, over and over again, because they can always be more and more challenging if you make it so. This is specially true for the final fantasy series. You can replay it and not use certain items, or do certain things to make the game even more challenging.
Perhaps the king of brain games is the very well known Supa Plex. This is probably the most dificult game of all time. You need to have a huge brain, plus cat top class reflexes and a lot of other features in your brain so you can beat this game. I never did it and I play it since I am four so see if you can do it yourself! Don't blame on me if you brain melts down however!