Did this salesman work for VW in the past?
Winter pack is what VW call heated seats/headlight wash/heated washer jets, it's a bundle available for factory order.
Confusion used to occur because if you ordered leather + xenons on a VW as these would automatically get you heated seats and headlamp wash (wash is a requirement of any factory xenon installation hence why aftermarket HID kits aren't strictly legal but that's another matter).
So I categorically say winter pack is not an option but all cars have heated seats and headlamp wash.
Full electrics?? I presume he's referring to electric seats which they all have.
They all have Bose.
Centre armrest was an option but most seem to have it.
The brochure is here and options are listed at the end
http://rs246.com/downloads/AudiRS4B5/Do ... K_2000.pdf
ones i have missed are
load net
self dip rear view mirror
isofix child seat prep
6 CD in boot
Alcantara pack
Black optics
That steering wheel IS rare but not sure I like it as the 4 spoke design is just like the one you get on TDI SE! Only time I have ever seen that before is on French RS4 being ragged around a test track on You Tube.