The mw doesn't matter and has no bearing on it since the capacitor is used to prevent voltage spikes. I am using 10uf 16 volt "can" capacitors for all my diodes including my blu-ray. The capacitors you have will work fine...I wish I had a few that small...lol
20/30... if the price is right... maybe more if the price is really right! I like to use tantalums in this application, and I believe in nearly inexhaustible spares supplies!