shrek  

Do you mean Shrek 4, the new one that is out? And if so, I think it's best to watch the movies that came before it before watching the new one that's out. Just because it gives you more insight on the character and what they've been through. I will tell you though that, while I loved the first movie, I was not a fan of the third movie at all.

you should watched the first and second first..get to know the characters and the story line..believe me!it worth it..and you would enjoy every movie..

Shrek 1 is the best.For that matter many sequels which try to cash on the success of the original first ones are not that good.

Actually, for the most part, I wouldn't bother watching the third and fourth movies. The first two are a must-see, especially the latter, which I consider the best of the series. In any case, yeah, you should watch them before watching the other two. "Shrek the Third" was terrible, and "Shrek Forever After," although an improvement over its predecessor, doesn't match the level as the first two.