Here is information about some of the best and most noteworthy film adaptations of Beowulf:
Beowulf and Grendel
Director: Sturla Gunnarsson
This is purely a medieval action flick with plotting loosely based on the original epic poem. In this adaptation, the character of Grendel is stripped of most of his supernatural elements, and thus the action here is totally down-to-earth rather than being an epic story of monsters vs. men. The movie is entertaining in a period piece kind of way, and the cinematography is beautiful with most of the film having been shot in Iceland and Canada.
This animated IMAX version of Beowulf (in 3D!) is WAY over the top. Other than the setting and plot starting point, this adaptation does not follow the original epic poem at all. The screenplay was written by Neil Gaiman and Roger Avary, and reflects their dark and satirical visions as reflected in some of their other works. The movie features an impressive voice-cast, including British actor Ray Winstone as Beowulf, Anthony Hopkins as King Hrothgar, and Angelina Jolie as Grendel's Mother. Very entertaining stuff, even though it's only marginally useful as a reference for the original epic poem.