You should look for a school that has a high pass rate, but the pass rate itself is not the only criteria you should have. You might also want to look at the school's reputation for programs that have prerequisites that are similar to what nursing requires. The higher those programs are rated, the better the overall chances that their prerequisites are also extremely good too. Among the other things you need to look at are things like program cost, cost of living for the region the school is in, distance to clinical sites, and so on. Although it is not likely, it is possible that you could have a very good, highly rated, program that costs a lot because the clinical sites for a fair distance away, the tuition cost is high, and the cost of books is high.
In the end, what you get is what you put into it. You could attend a rather poor school, do your best to learn as much as you can, and ultimately pass the NCLEX – RN. Conversely you can go to a highly rated school, barely pass the courses, and fail the NCLEX – RN. It's really all on you!
I probably succeeded in confusing you more, but I'm glad that you're doing your homework now rather than waiting until the last minute. Good luck, and choose well!