I recently read that we have greater than 200,000 proteins making up our combined metabolism.  Yet, we only have about 30,000 genes.  How can 30,000 genes code for 200 K + proteins?

Latest estimates are that humans have just under 20,000 genes that code for proteins. What is important to realise is that many genes can code for more than one protein. The two commonest forms of this are:-
1.    Alternative splicing. When the DNA is transcribed into the fully processed mRNA, along the way introns (the bits in between the coding exons) are removed. But in some cases one or more introns can remain and thus a different protein is made. Similarly some genes will remove or add in an exon so again a variety of truncated or extended proteins can be made from one gene. The factors that control alternative splicing are species-, developmental- and tissue-specific. Thus different proteins can be made at any one time in different tissues, or a single tissue can alter the proteins made during development.
2.    Post-translational processing. A single protein once made can then be chopped up by enzymes in the blood or tissue to a number of smaller fragments. Each of those fragments can have differing biological functions – so again one gene can make a number of proteins. Similarly other enzymes can alter the protein by sticking phosphates, sugars or other groups onto it. Again that can be species-, developmental- and tissue-specific, and again each change can alter function.

Thus you can see that from one gene very large numbers of subtly different proteins each with different functions can be made. I would guess the total is far larger than 200k!