Walt is a solid player, he could make a move there, but I bet he at least had the straight with you. If you cashed I wouldn't worry to much about it. If you were severely short-stacked I would call, but It looks like that fold left you with over thirty blinds. I see a lot of people saying they wouldn't have folded, but (not saying any of these people are) we all know there are a lot of donkeys around here. Plus, the best players know how to make big laydowns. My advice would be to, trust your judgment, keep a level head, and don't let people know what you folded.