noob patching from stock game

[PurpeAtome]

Hi all,
I picked up Il2 Sturmovik yesterday for 75p (!) from my local CEX store on a whim.

Wanted to patch it to the latest version, but i'm a bit confused, as far as I can tell, the latest version is 4.101, can I patch version 1 to this, straight away, or are there other patches I need to do first?

Loving this game so far (and Silent Hunter II i also picked up for 75p!)

Version 4.101 seems to included content from 1946 too, does this mean I have to buy 1946? If this is the case, what is the last patch just for Il2 sturmovik?

Sorry about the probably obvious questions, but I haver really only just discovered this game!

Thanks for any advice in advance.