Hi Feldrin,
I don't know a whole pile about Scotland either but I do know it is quite similar to Ireland but just that everything bit more bigger and extreme and that includes the weather.
- When is the best time to go? We were planning on going in the winter but it seems that there are hardly any camping’s opened around then and that there are not a lot of hours of sunlight to trek around.
There is a reason that camps sites are not open during winter .... because there are not many people willing to battle the elements. You will have alot of rain andif you venture far enough up the highlands snow which is really no place for camping unless your an artic explored
- What is the best way to go? Boats seem quite cheap but only if its off-season, like winter. But then there’s the problems listed above. Airplane seems cheap, up untill the point they add the polution-tax and whatnot and the price suddenly tripples.
If you are going by boat from Holland where will you land? I believe that a train journey from the south of England up to Scotland is one long trip and could prove to be more expensive than your boat trip
By plane is great for convienience but it reduces the amount of bottles you can bring back.
- Would I have to pay any extra taxes for ‘importing’ a few bottles? From Scotland to the Netherlands that is. I mean, the stuff should be cheaper over there and carrying around a few bottles will probably add significantly to my feeling of joy and happiness.
As your in 2 EU countries there should be no tax implications but believe it or not Holland has cheaper prices than Scotland (because there is higher duty and tax in UK) .... My other halfs sister lives in Amsterdam and we go each year and I stock up on whisky.
- Something about distilleries. If I wanted to have a look around, are they always open to public or are there certain tour-moments or visitor's centers? Any distilleries I'd especially have to visit?
Sorry can't help here .....
- There seems to be a possibility of wild camping, with certain rules and regulations attached. Anyone know anything about it?
?????

just watch out for hairy animals roaming at night ... the're called Scotts
I presume you mean just camping in farmers fields etc ... that is done here in Ireland too ... as long as you ask the land owner and they agree there is usually no problems but finding a land owner in the middle of a mountian can be tricky

Technically state owned parks ban camping but you will get away with it as long as they are not in the middle of a town and you don't litter.
- What would be a good region? I love Islay whisky but we were kinda planning to enjoy some mountains in the highlands. Walking from Islay to the Highlands seems a bit far. And I think Islay deserves a trip on its own.
Sorry out of me dept here also
Any other random tips or snippets of information would also be greatly appreciated. My general knowledge about Scotland probably amounts to ‘that far off holy place they make really really good water of life, oh and mountains'.
Hire a car and at least you can sleep in that if needs be .... not very comfortable but it could save you a few miserable nights and a safe place to stash bottles beside lugging them around. You would be surprised how heavy just 3 extra bottles in your luggage can be..... Also you may not get lifts in the more remote regions in scotland if you need one and people tend to ignore 2 guys with a load of camping gear slung over their shoulders ...
Sound like a great adventure though so if you postpone till spring or go in Autum that may be more favourable.
Good luck what ever you do....