My 2002 4.4 v8 appears to have this option on the screen, I always thought these were only on diesels? How do they work?

As you have it on yours, you should be able to tell us; I now petrol versions could be equiped with this as an option.
Does it work?
If yes, does it run on petrol or diesel? RR 2012MY TDV8 AB ipanema sand
RR 2004 TD6 sold now

If you do have it, it will run on petrol - they are avail in both versions.

Unless someone has been at your RR with a diagnostic tool capable of activating the park heat function (I assume this is what you mean) and had a play, you will likely have a FBH installed.

Set the timer and give it a go. If it sounds like a small jet is starting u der your RR, you have a FBH - congrats! Otherwise you'll get a fault code - and you'll need a diagnostic tool to have it read... :-p 
RRC 2Dr, RRC 4Dr,
P38, and 2 L322s
(wife thinks I'm nuts - prob right, too)

Mine is a 2005 petrol car and has fbh option which is brilliant in Winter.