How to back up hard drive before upgrading to larger HD?

This is an easy question from a virgin at disc burning and hard drive back up (I have no shame). My 2006 MacBook (original version) has the 2 GB Intel core duo. When new, I needed to format the HD with one half for each OS: Mac / Windows. I almost never use Windows and I recently upgraded to Snow Leopard X (10.6.3) OS. I also use an external La Cie CD driver via usb with no problems. To accommodate software updates, etc. I need more HD space. Question: Can I use "disc utility" to burn a disc containing my entire hard drive, including Mac and Windows data?? If so, do I then reformat the new hard drive as I did when setting up the Mac in the first place??

Any help is appreciated. I want to keep this MacBook going.