No, Volstagg.
Stellan Skarsgard to me is a better fit for Odin, in how he's portrayed as a character in Marvel Comics. Sure, some artists drew him on the tubby side, but he was still an intense, powerful, at times world-weary figure, a kind of role I think Stellan is ideally suited to capture.
Brian Blessed, meanwhile, is a wonderful character, but in recent years has become known more for that over-the-top persona than his serious acting. He's a big, fat, jolly luvvie, with the ideal amount of booming bluster to perfectly inhabit a character like Volstagg and turn him into a scene-stealer. Next time you read a Thor comic, imagine Volstagg's lines proclaimed in Blessed's voice: it's PERFECT.