Easy way to get perfect game
To get 300 points easily pick Gun Jack and/or Jack-2 (P-Jack works as well) step to the first line to the left or right, Aim the red line to the pin between the middle pin and the pin to the right/left then get the arrow pointing to the yellow each time and no matter how fast the ball is going, you will get strikes each time.

Unlock Tekken Bowl mode
Beat the game with Xiaoyu chosen as your first character. This will unlock her school girl costume. Choose Xiaoyu in her schoolgirl outfit by pressing start to select her. Beat the game with her as the first character in her school girl outfit. This should unlock Tekken Bowl, which can be selected from the regular Tekken Tag menu screen. Once you've done this, you're home free. Just go into Tekken Bowl, choose your characters, and start bowling. You even get to use a fun-filled silver bowling ball to smash gold bowling pins shaped like some weird looking guy (we think it's Heihachi). Depending on your character, you can be left-handed or right-handed, and the power of your throws varies between characters.