Is 5.1 Really This Bad?

I've not paid much attention to multichannel, because I'm not much of a vidiot and because two speakers is all I'm likely to get (or so I've been told). But I was in a (low-end) store with a nice comfy surround-sound room today, and sat down to watch a few minutes of what I gather was The Phanton Menace. There were plenty of sound effects going on all around me, but I noticed that they had very little to do with what was going on on the screen. Even when they did, there were obvious discontinuities: A vehicle would drive off the screen to the right, and its sound would seem to disppear, then reappear in the right speaker.

Needless to say, I was less than impressed. Is this wretchedness typical of what one hears on a movie soundtrack in a home theater? Does 5.1 require a sort of suspension of disbelief, where we teach ourselves to ignore the discontinuities because the whole thing sounds cool? Or is this just a particularly bad DVD?

Speaker setup appeared questionable: The fronts were place well wide of a very wide screen, and one of the rears was partially obscured by an overstuffed leather chair.

I'd be the first to concede the inherent limitations of two-channel reproduction. But after this experience, I'm feeling rather better about those limitations.