I haven't stayed there myself, but if price isn't a concern and you're looking for the closest hotel, I think it's the Sheraton. Some friends of mine stayed there and liked it a lot.
I'm sure others here will have many more suggestions!
There is a Sheraton and a Hilton within walking distance to Universal Studios I know there are also some really close hotel that are less expensive that have shuttles... like Best Western and such... try www.orbitz.com type in Universal City, CA
There is some really great stuff at this link for Universal Hollywood!! Like Operating Hours and Park Information,ticket specials,and City Walk!!
click below http://www.themeparks.com/unica/default.htm