My algorithm is basically as follows :
input password hash(password) AES on file using the hash
in this case, does the hash algorithm matter as long as it's distribution is somewhat uniform?
would some weak algorithm like md5 be fine, or should a better algorithm be used?
in the case someone tries to brute-force, slower algorithms will perform better, so I'm not taking this into account as it can be offset by using more rounds.
I'm doing that because AES needs a 128 bit key (or 192 or 256), and the user might not want to input a password this size.