Just started using LaTeX, and it annoyed me how the vertical-alignment of the \underline{} tag is not always the same, depending on whether the text ‘dips downwards’ or not (don’t know the correct term).

Anyway I found a fix, basically use \usepackage[normalem]{ulem} in your preamble, and \uline{My Text} instead of \underline{} in your normal text.

via Getting to Grips with Latex – Formatting – Latex Tutorials by Andrew Roberts @ School of Computing, University of Leeds.