Someone may have to correct me on this,
i believe it only takes one "frontpage" vote to frontpage a node. As for approving, approve all that seem to be relevant or amusing or whatever it is you use as criterion. i generally don't approve that many nodes because there are some people (and far more than i can mention here :) who are really fast and efficient at taking care of that in a good manner. i have deep respect for those people who crawl through the newest nodes doing this a lot, they do a fantastic job <round of applause>.
Hope That Helps,