I want to install windows 7 over a pre-installed Windows 8

I Bought a new PC pre-loaded with windows 8 and I actually want to get rid of the OS and load my own windows 7.

I was looking at the Disk Management and found that there are 6 partitions on my laptop.

300MB Healthy
600MB Healthy (Recovery partition )
186.30GB NTFS Healthy (BOot, pagefile, crash dump, primary partition )
258gb NTFS Healthy ( Primary Partition )
20.00gb Healthy ( recovery partition)

There were two options when creating a recovery disc. I actually want to wipe out the entire partition and have only two partitions of my own, enough for windows 7 OS ( 50gb ) and another partition for data.

How do I burn the ENTIRE recovery partition to a dvd or usb drive incase if I Switch back, I Can just pop the disc/usb and make it factory reset.