Once you stuff gets moldy and smelling, you might as well throw it out. Plastic and metal can be cleaned but usually not porus stuff.
Clorox is a good chemical used to kill mold. Or at lease slow its growth. You can scrub the basement with clorox and a brush but be sure to provide adequate ventalation for your eyes and nose (lungs). SCUBA gear or a mask & snorkle tube would work. After you kill the visible mold, you could use block sealer such as (UGL waterproof paint) to seal out moisture (make sure it contains portland cement) and paint the wall and floor surfaces (make sure to add plenty of mold inhibitor to the paint).
After fixing the problem, constant maintenance is a "must" (no pun intended). This may include a dehumidifier in summer and heat in the winter (maybe use a Kero heater).
Also make sure that water isn't coming into the basement. No water = no mold.