So I was looking for mods and I read that the game should be the latest version which is 1.2 (maybe?) and was just wondering if the vanilla download from GOG of Fallout 1 is that version?

It's funny but I marked your post as a solution even though you clearly didn't know if it was ver. 1.2 but your right it should already be on 1.2

iirc, it's the latest official version but it's censored (euro version? I forget) so use of the semi-official 1.2 patch by TeamX is recommended. All it does is turn the game into uncencored (US?) version. It's also requiremnt for TeamX unofficial patches for Fallout 1. However, I just checked and the patch available on NMA is NOT the latest (last as teamx has disbanded) version of the patch. You can find the latest from teamx site (google translated as site is mostly in russian). It's the "Fallout v.1.2.1 universal patch (eng)".

Alternatively, you can download it from my site where it's the "fallup121rc3.7z".

There is also FIXT megamod if you want to all the patches (official and unofficial) and mods in one package.

I ment the semi-official patch. The one on NMA is 1.2 and latest is 1.2.1 and the unofficial patch 1.3.5 requires the later. Biggest difference between 1.2 and 1.2.1 is that later contains the children patch.

Edit: Actually, I just downloaded the supposed unofficial patch v. 1.3.5 from NMA and file I got was v. 1.3.3 so either that particular mirror or all of them have old version. Difference is quite huge as 1.3.5 is 1.5 megs bigger unpacked than 1.3.3. Same goes for semi-official patch 1.2 and 1.2.1.

TeamX naming system may be partially at fault as they kept file name the same (fallup13.rar) from version 1.3.0 to 1.3.5.