I had an interesting issue where in ie7, the element that I was displaying using the jQuery slideToggle function, would seem to jump out of place once the animation had finished.
As I was displaying a list, I first assumed that in ie7 the element was adding in the default list margins and ignoring my css. However no amount of fiddling with adding css margins in the slideToggle callback function seemed to sort the problem.
Googling allowed me to find a solution here that worked, although I have no idea why it works.
Basically I needed to add a min-height of 0px on the parent element, and set the height of the ul that I was trying to display to 100%.