Roxyl said:

"I pulled out the soggy grass and put it in one of those black plastic composters along with old leaves, shredded newspapers, sawdust and new grass clippings (was that right?)."

You may not have needed the fresh grass, but if not and it starts getting your attention you can add more browns. That is the beauty of composting, you can always make it right later.

Then Roxyl said:

"What do I do with it before it heats up and really starts reeking?"

Dump it out now and act like you don't know where that strange smell is coming from? I don't imagine it will smell bad very long anyway. I have made my fair share of "hum dingers", the kind of odors that make ones eyes water and ones nose refuse to inhale until a considerable distance from the source is evident. Once fresh air is allowed to mix into the mess all is well again, sooner or later. Seriously, you could pack leaves into the bin in an attempt to absorb the odor, but there will still be that "whiff" in the air for awhile. IMO, the sooner the deed is done the better...

Blutranes