Johnny Cash songs!!  

i only came to know Johnny Cash after watching the movie Walk The Line. i found his songs very good and inspired by the movie i tried to download some. but funningly some song which i downloaded were not sounding as nice as they did in the movie!lol but maybe the reason behind is that i don't know exactly the title of them and i searched & downloaded only by pure guess. i mean the title was good so i thought song must be too!;) so here i m asking u to suggest me any of ur favorite song sung by Johnny Cash &/or June Carter. or other ones that u think r good. also can u tell me the title of one song Joaquin Phoenix(jhonny) was singing on stage with Reese Witherspoon(june)? i know there were many :D but i mean the one between which he kissed her and she got angry and left the stage!!:)thank u!!:)