Shinjuku has LITERALLY EVERYTHING and that's not an overstatement. It's one of my favorite places to hang around because there is so much entertainment, whether you want to eat and drink, shop, club, or take in historic sights.
NGL, I think Shinjuku has some of the best food! At the very least, it provides the most options of food because you can find pretty much anything you want in this area.
Shinjuku has so many areas to shop that you may actually drop; especially after you see how much you spent after a day here!
Whether you want to stay in the middle of the action or one of the more quiet neighborhoods surrounding Shinjuku, this is a great area that is accessible to the rest of Tokyo for added convenience.