I quite like the shape of it but not the pattern. And it depends on how tall you are too: M&S dresses often come at a very frumoy length if you are not tall. If you don't mind paying a bit more, the White Company have some beautiful jersey dresses.
I would wear something like that with boots providing it was short enough to see a bit of leg over the boot, so I disagree with Shandy on that point. Then again, I have quite slim knees and lower legs, so would want to show that bit! I think dresses (other than maxi) look really odd with long boots if the boot top is under the hem of the dress - it's a very 70s look.