IE has some non-standard methods that should be avoided, and standard DOM functions used instead. Since those are generally supported in IE as well that's most likely mot a problem.
Here is the DOM documentation of HTML tables. Note that "cells" is a property, not a method, so it does not have parentheses after it. Once you have the rows, you can dig into those to get at the cells.
This article is also helpful in creating cross-browser compatible code.