The graphics in Ultimate Party Challenge look very much like most other Wii games. It has cute little Mii-like characters and lots of bright colors everywhere. You can customize your characters with different outfits, hair styles, and faces. Granted, there aren't an over-abundance of choices, but it's enough to find something you like. You can also buy some new clothes after you've earned coins. You don't get to "try on" the different outfits before you buy them though. Just make sure that you don't create a character that looks exactly like one of the built-in characters. When you go to select your character in the game, it doesn't show the names above them, so if you've made one that looks exactly like one of theirs, you'll have trouble knowing which one yours is easily. The graphics in the mini-games are decent. There's nothing spectacular about them, but there's nothing wrong either.
The background music is very upbeat and peppy on the main screen. For the mini-games, you get different sound effects for each game, like the foot fighters where you get to hear the sword slash when you hit the button. Little additions like that were my favorite parts of the game.