Shakey's pizza in Shinjuku is absolutely amazing. It's pretty much the only time I ate "western" food while I was in Japan.
Unlimited pizza and it's friggin delicious. I forgot the price, mainly cause I was gorging my face. Luckily snapped a pic of my place setting.
Definitely recommendation.
EDIT: unlimited pizza as well as these daaaank potato wedges. Dunno if they have them 24/7 but they were to die for.
