You'd better (had better) get moving, unless you want to miss the train.
Would you like some tea? No, I would rather have some coffee instead, please.
Can you understand the meaning from the context?
perhaps 'had better' mean that something we have to do,but 'would rather' mean something we prefer to others,or those things we really want to do.but if i follow this idea,'prefer' sometimes can replace'would rather'?