is the chain and chainring new or is one or both of them used
if one is worn the chain will make noise, lots of it if its bad, especially if the chainring has lots of wear and then you put on a new chain
old brake pads or new? the big block shaped diacompe style? if so, they are quite hard and take awhile to work right, roughing them up with some sandpaper helps sometimes, and if youve got a chrome plated steel rim you will never have real good braking power compared to an alloy rim with a good brake either