The Vikings were mostly pirates for the most part. They went around having pirate battles and etc. They raped women and whatnot, and what is meant by war is probably ship battles. The Anglo-Saxons on the other hand were conquerers, wimpy ones albeit (I don't like what they stood for; hell I think the British Empire got their ways from them). But the Vikings were, I admit, wicked and cool explorers who never minded having a badass ship battle.
There ships were actually quite vulnerable in ship/naval battles, I wouldn't really call them pirates more like bandits that retreated into ships rather than the countryside.
Pirates tend to focus on raiding ships/trade routes, while it was not unheard of for pirates to attack coastal towns it was not common.
While vikings went right to the source the settlements and took what they could carry, until they encountered organized resistance and retreated to their ships.
Although Vikings were famous for their pillaging most of Northern and Western Europe, their legacy lives on due to their ability as conquerors. Normans were the descendants of Vikings whom were ceded land by the Merovingian dynasty over France. This set the stage for the Invasion of England, etc. Before that, Vikings vied for the throne of England for centuries, often defeating English armies and once in stilling a Viking king. Their abilities as conquerors allowed Vikings to establish footholds all over Europe (and North America)