Thank you very much to all of those who responded to my question;  it turns out that it is my Acrobat Reader resolution that is at fault rather than a LaTeX issue.

But in any regard if there are any suggested LaTeX packages (I have found a few good ones with queries on Google)  I'd love to hear about it.

Thanks again!

--Elizabeth

I'm looking for recommended LaTeX tensor packages.  If I, for example, type

\underline{\underline{\underline{\underline{E}}}}

sometimes the lines are uneven and the above expression therefore doesn't look quite right. 

Any help would be much appreciated!