having trouble putting cheats on my r4 can anyone help.

The problem is I do not know how to extract Winrar type file and my computer can extract Winzip type as far I know.

download winrar from www.rarlabs.com and follow the tutorial in our tutorials section

i dont have a system folder just a moonmemo folder, moonshl2 folder and a r4imenu folder please help me

When you installed the firmware it should have created the system folder for you. If your using a R$ then goto "http://r4team.com/eng/index.htm" to get the latest firmware, then unzip it, copy it to root folder of sd card and then cheats will go into system folder. Hope this helped.