I must have been lucky because of the many weddings I've been to between family and friends, none stand out as obvious worse ones. Sure, some were not the most exciting affairs with a standard ceremony + meal + dancing formula, but they were by no means bad.
As for the best, it's a tie between two, both friend's weddings. What stood them apart is that after the usual ceremony the party was held outdoors with bands playing music live, with the focus not on fancy and expensive stuff, but on letting people have fun with the newlyweds.
Read and lead rhyme but read and lead don't