I wanted to conect my front USB with the Motherboard,
but i don't know how.

Here are the Pins!

My Tower:
oUSB+
oUSB-
oVCC
oGND(ground)

The Peg2 Motherboard:
.USB+
.DMI 1
.DP1
.USB-

Wich one i have to conect?
Please help me i don't want to frie my Peg.

I will guessing: Maybe dMI means MInus and dP Plus?

But I strongly adivse you to to look at this:
http://www.hardwarebook.net/connector/bus/usb.html
And check the voltages on the connector with voltmeter after connecting cables to the mainboard or better with ohmometer before you you will connect it. Even if you'll make some mistakes, they will not do any harm to your Pegasos until you plug in some device into USB connector.

I connected this way external USB connector to my Peggy about year ago, and haven't got any troubles.

All went ok the front USB is working now!