The R-C filter on the AC line is 'Trap' for noise or spikes which otherwise might be passed through to the electronics and cause damage.
The 56k µfd cap is to smooth the otherwise 120hz DC ripple coming out of the bridge, this cap. attempts to keep the level of the DC voltage 'pure' or constant.
The bleed resistors function is to provide a dis-charge path when the PS is switched off.
BTW, Why do you think it is not charging?