When fighting against unbelievable odds dont panic. Choose the long sword. Keep using the slash-high attack to cause the most dammage. You may get down to only one man left, but you can still defeat the enemy captain. After you win, select send a prize crew so you will have enough people to sail your ship.
Don't attack a nation your home country is allied with, it will upset both of them.
Don't wed till you've got all your promotions, your oppurtunities will be much better. Make conversation with all the governors daughters, however, they might gather important information for you from the governors mansion.