Buttons are one big part of the games, and it is often overlooked.
All the popular and quality games all have really amazing buttons. When players first enter game, the first thing they see is the game screen, or introduction. However, the first thing they play, is the button. Having fun, beautiful, responsive buttons make the game a lot a lot more fun. World of Warcraft, the largest MMORPG, has probably the best well-made buttons, which is a big contributor to the overall fun of the game.
A great button would be something that has a good picture or funky text. Times New Roman font is not a good text font, and some tiny pixelly picture is definately not a good picture for a game button of high standard. The great button might have a border, if it like an ability button. And once pressed, the distance between the picture and border shrinks down on one side, creating the looks of being pressed down like a real 3D object. The button should highlight when mouse hovered over.
As for sounds played for button press and released, the sound should be not so loud, yet not too quiet to be unheard. So something in between a roar and a clap would be good button sound.
