The lower the hip score the better, i.e. 0 - 0 is perfect, and the worst possible score is 53 - 53 (total 106) but each hip is scored separately, so you could get an odd amount on each hip i.e., 3 - 19 (total 22). Each breed has an average score, above which you need to consider carefully whether it should be bred from. This varies depending on the number of dogs scored. There are many hundreds of Labs scored annually, so the average is a good guide. It is currently about 15 in total.
This site will give you a lot of information:
http://www.lab-health.co.uk/Tests/hips.htm
Eye testing is done at about 8 weeks and annually thereafter unless there is a particular problem in which case you might do it every six months or just before mating to make sure if it is something that can occur later in life or get progressively worse.