W-4 and taxes

[Shotput]

How would you guys suggest filling out a w-4 as an investor? I have always chose to have less taxes taken out so I can use the money to gain interest. I want to maximize my situation investment wise. How would you fill out a w-4 based on this situation:
I work, my wife works, I have no kids, we own a house.

[noppenbd]

Use the IRS' withholding calculator:

IRS Withholding Calculator

Using last year's taxes and estimates of this year's deductions you can get pretty close to zeroing out your refund. You can go further than that (and owe money) but you may have to pay a penalty if you get too extreme.