Firebug / Page Speed / mod_expires

[PAJ]

I recently started using Firebug and Page Speed to check my websites and I typically get this message as a result of the analysis:

"The following cacheable resources have a short freshness lifetime. Specify an expiration at least one week in the future for the following resources:"

The analysis then points to various css, js and jpg files.

I then began reading the following (which gave me a headache):

http://www.askapache.com/htaccess/speed-up-sites-with-htaccess-caching.html#menu0-el2

My question is, given the servers being used here, what is the best implementation of "mod_expires" (preferred by Google.)

Also... Should I concern myself with implementing gzip on my websites, and if so, how.

Thanks in advance for any assistance.

PAJ