Right now My wife & I are using no dependants on our paychecks & we have 2 kids, she is set up as married & I am set up as single
We have decided We need more money on our paychecks to get by & don't care about a large return anymore...
If we both select married & select 2 dependats each will we have to pay at the end of the year? Together we make a little under 100,000
I want to make it so our return will be little by we won't own anything!

You should definitely submit new W4's to reflect your current situation. There really is no point in having too much tax taken out all year long just to get the excess back later - it's like loaning your uncle money without getting any interest on it. The goal should be as you state - not to owe much when you file taxes or get much of a refund either. If you follow the directions on the W4 form for the personal allowances worksheet you should select Married and it suggests that you enter one for yourself on line A, 0 on lines B and C, and 2 for the children on line D for a total of 3 allowances. Then go through the worksheet for two earners to check that this works well in conjunction with your expected deductions or other income. If each of you does this it should work out well for you.

The form with directions are here: http://www.irs.gov/pub/irs-pdf/fw4.pdf

Its hard to answer without knowing what deductions you have.. If you own a house with a mortgage, that can count as another dependent.

But as ebaines said, it makes no sense in withholding less to get a big refund. When you do that, you are making Uncle Sam an interest free loan. If you take the extra take home and put part away into an interest bearing account you have some money to pay if you miscalculate and under withhold by a little. And if you don't you have savings to make up for the lack of a refund.