Beyond the actual ranking of a school (which, in my opinion, would be ridiculous for admissions committees to consider, seeing as so many law school deans are against USNWR's rankings in the first place), the very important numbers are the average GPAs of students at your school.
If you go to a school that hands As out like candy (grade inflation), your GPA counts for less - if you go to a school with a lot of people getting Bs and Cs, and you still manage a 4.0, that looks much better!