If you own a game boy color, this game should not be missed.
Original(1985)
The title spells it out really. This is the original game, with all of its secrets, cheats, etc. in tact. That same good old music is still there, and everything you would expect from the original. It still has the great game play, fun puzzles, and good characters just like the original. Nothing is changed from the original, and that is what is great. But wait!, there is a lot more to be found than just the good old original game.
Challenge
In this version, as you beat each level in the original mode, you can come in here and try to get the highest score you can, by finding Yoshi eggs, red coins, regular coins, killing enemies, and going through the level as fast as you can. It is very fun, gives you a little something more than the original. There is a bar that fills as you finish the levels, and there is no doubt something to behold once they are all finished.
VS Game
In this mode, you can link up with your friends, and play against them through different levels. You need to beat your opponent to the finish line, by using any means necessary to block him off, etc. This game is very fun with friends and family.
Ghost
This mode is just about the same as vs, but you are racing against a ghost, instead of another player, and you are playing by yourself in this one. This version is for people like me who do not have any friends to play games like this with.
Bonus
Now to the different things that Nintendo has added to this great classic. In the toy box there is a calendar, that allows you to put events on it, and print it out. This has nothing to do with Mario, but it is a good use of the printer, and can come in handy on the road. There is also a fortune telling section, where you pick a card and you either get a lucky, or an unlucky card, and there are quotes such as "Fortune is hidden in bricks unbroken," these are hints that help you in the game. There is a Yoshi section in which levels fly by, and you hit "a", and gradually it slows down to show you a certain level, and where Yoshi's egg is on that level. This is very helpful for challenge mode. Lastly there is an icon with a hole( which looks like jerry's from Tom and Jerry) with a question mark on it. This has a round table with peach as the head. You click on different toad characters and you can print banners out, or change that startup screen, small things, but fun to do as well. After you beat the original game, you will also find that a Luigi icon shows up on the main title screen. This is "Super Mario Brothers for Super Players." It is just like the original super Mario brothers, but it is harder, and definitely adds replay value to this already great game.
Overall, the game is great. This game nails the original game perfectly, and adds many more features to go along with it that make the game much better, and worth your money. Although it can be frustrating at times to do one level over and over again, it is worth it all in the end. If you own a game boy color, this game should not be missed.