Preferred method for removing mold & mildew from album covers

I suspect you will actually do more harm than good trying to clean the albums.  The best course of action is to try and replace the covers.  Otherwise, I'd leave them alone.  

If you do a little research on the archival preservation of documents, books and paper products, you should find some suggestions for dealing with album jackets. I don't know how effective some of the methods are, or whether they risk damage to the colors or finishes of the jackets. (My suspicion is that many archives would probably start with fairly mild approaches that may be insufficient). There is considerable literature on this. Let me know if you cannot find it.

In the meantime, I would keep the records far away from the contaminated jackets, and even if 'treated,' keep the contaminated jackets away from other records/jackets or other materials in your home on which the fungus can grow. 
Let us know what you find. 

I've replaced quite a few covers surfing in good will or similar stores. For smell you can use Ozzium. The way it works that you should place your smelly items let's say inside your car or bathroom sprayed all over with Ozzium and than close the doors for 20...30min. The car would work best
With goo-b-gone I cleaned large number of album covers as part of my business. Nothing work best there.