For the rooting: download SuperOneClick, open it press Root and follow the instructions.
For flashing Kernel and unlocking bootloader follow the instructions in this topic, the first post and the links inside the instructions:http://forum.xda-developers.com/show....php?t=1068553
For going back to stock ROM - it's easy, download SEUS from SE site, install, open and follow the instructions, as you choose to install firmware although you already have the latest version.
And last but not least - don't be so lazy! We all didn't know what to do here in the beginning, but yet we found what we needed. And you want everything without any effort.