Protecting Your 401k In a Market Crash?

Here's my situation... I have a family of 4, built a home a few years ago and am trying like heck to pay off our credit card debt (~$10k). We have very little in savings, but quite a bit saved in 401k (> $100k).

I would like to buy gold because I believe there will be a global market crash... but can't get at my 401k without paying a large tax & penalty. So I'm not sure this is the best, or smartest option.

Any ideas on what I could do? Besides gold, where else can one go to protect their retirement? Thanks in advance.

(I've been skeptical of 401k plans from the beginning. I knew something like this would happen some day)