When did the vikings used maces?

Never, or at least neither archeology nor written sources have any trace of maces in them

And how do fend off blows from a 2 m axe?...,i inmagine that youre shield looses alot of his functionality...when you try to block him with your shield

you block with the shield boss, or using the shield in such a way that his cut go across the grain in the wooden planks in your shield, he will still wreck it, but it will buy you time to get inside his reach and cut or stab him

I somewhere read that they used a mace in one hand to disrupt there shieldblocks...mayby even destroy the shield...and in the second hand a sword to stab/slash right after it.....of course this could just be another hollywood story i dont know.

Hollywood

And the shield quality of course is not always the same...but who had the best quality shield?
I always aks myself,how long somebody could wear off blows from sword/spear...before it breaks

Good question, I do not know, the Roman "Plywood" Scutums would have been quite strong and resilient, but those who have actually constructed an authentic copy of a Viking shield have found them remarkably resilient, spears and arrows will go through, but not hit you and a twist of the shield may break the speak (described in Sagas). Viking shields were from buckler size to 1.2 m and circular made of wooden planks 8- 15 mm thick as I recall, I have a friend finishing his Ma Thesis in archeology on Viking shields, I could ask him if you want a real lecture ;-)

When i remember it right....i think the only time i saw a shield smashed in a hollywood movie...was in the 13th warrior lol

I honestly do not know, I tend to avoid Hollywood "historical" films, especially about something as dear to me as Vikings. I avoided Rome and City of God for a long time before letting friends talk me into seeing them, one I regret avoiding, the other I should have avoided altogether;-)

But i can inmagine that one good strike of a mace,could crush a shield immediately,mayby even breaks the arm holding it.....Before somebody things that are statements...NO...i dont know it

Maces are nasty weapons with high impact, well suited for caving in armour. However, a shield would be the best defense against it. Some of us do late Medieval re-enactment as well (not I), so I have tried some medieval weapons.

So when i had to choose i would prefer 2 weapons(lol i learnt to fight with 2 weapons...and i know that i can't compare it...to the old days)
But still i think when somebody is not properly trained in useing a shield...it would be not more that a burden for him...of course would he be in a better position when its raining blood..ehm arrows.

Well, I was one of the best two-weapon fighters there were and for freestyle it is superb as you can almost always get a "tap" in by all-out attack. In a real fight however, and thus in Heavy Style or Huskarl it is less suited. There is a reason history does not tell of many great heroes wielding two weapons;-) and against spears and/or arrows, well... let us just say that the Chinese wire-fight films, though beautiful are somewhat far-fetched.

Wich nation used the biggest shields?...wasn't it a persian one?

Outside my area of expertise.