Pauly are you kidding, discharging with a wire, as an electronic engineer, there is no such discharging method ever heard, discharging a HV capacitor need an electronic circuit with a resistor so the energy inside the capacitor would change into heat in a period of time. in physics we have a theory that energy wont disappear in the space, and it would just change from one form to another. like from electricity into heat or mechanical energy.
Bungee, if you want to clean your psu, as previous discussion i had with this forum guys, there is nothing to worry of, the capacitor are shielded with plastic, and be aware of touching its tips. the fan has a socket and you can remove it then clean it with a tissue and using oil in the middle part of it, called its router, you should remove its label, under that, there is a plastic cap. you should remove it and pour just one drop of oil in it. that simple...
but be careful.
Warning
Opening a PSU can be life threatening if you touch or bump a capacitor.
It is not recommended to do if you dont care so since it could easily kill you.