I think it's quite clear really.. I'd hazard a guess at:
"He has a set of rar files which he wishes to extract the ISO file from so he can burn it to a dvd and play on his, hopefully, modded console."
So, firstly, you'll need to extract the ISO file with winrar, and as I've already said there is a perfectly decent guide stickied in all other topics for this purpose.
Secondly, once you have the ISO file, I recommend using the free application IMGBurn (Google it) to burn your ISO to a DVD. Make sure you burn the DVD at 4-8x speed and use decent quality media such as Verbatim.
Lastly, if you come to play the game and it fails you have either burnt it too fast, are using sh!t media, have a corrupt ISO in the first place or don't have the capabilities to play the burnt disc, ie, a mod chip.
Sound alright to you?
Edit: rdn98, your sig is a touch too big - blanks lines count as lines of text and the max is 5 ;-)
