Security Deposit Return and small claims

I feel that my landlord over-charged for the damages that he claimed on my security deposit return. He charged us $250 for a dishwasher that stopped working and another $250 for a broken tile in the bathroom. He also charged a $75 cleaning charge (the house was totally clean) and he did not include interest. My question is do these damages fall under normal wear and tear? Also, what is an appropriate amount for us to get in interest? I am planning to go to small claims court.

You don't say which state you are in.

In California, the landlord must return your deposit within 21 days, or the balance if there are deductions, and MUST provide an itemized statement of deductions. If this is not done within 21 days, he losses the right to make any deductions, though he can still sue you for the damage.
Further it is his duty to fix the dishwasher unless you used it improperly which caused the damage. In any case he must provide actual invoices of the work done, and can only make these deductions. As far as cleaning is concerned, you only have to return the place in the same condition as when you moved in - it does not have to be squeaky clean if that was not the condition you got it in. Interest is about 5% per annum, not sure.
Whether or not it falls under normal wear and tear will depend on the original condition and what caused it to break