If your employer offers no match and your costs are high, you will probably be best off to make sure your and your wifes Roth IRAs are fully funded at $2K each each year. Then put the rest of available funds into the 401K.

The Roth $$ are after tax, the 401K $$ are pretax, so decreasing your 401K contribution will reduce your take home pay. However, in the long run, Roth is the better investment--especially in your case.

You should be 100% in stocks. The choice between Foolish 4 and S&P Index fund is up to you. Foolish 4 requires a brokerage account (usually at a discount broker) and usually becomes cost effective only after you get to about $10K. Vanguard Index 500 can be a good place to begin while you accumulate that $10K and while you get comfortable with the market.

You may also want to look at putting some of your funds into technology sector funds. They are shakey at the moment, but have done very well over the last few years. Perhaps up to about 30% of your contributions could go there in a Roth.

Best of luck to you.