I write for this site:
http://www.ehealthstar.com/

which sometimes, when my connection is a bit slower, needs over 30 seconds to load. My question is, which online tool can give me the best and detailed instructions about what to change.

I've found these two:
http://gtmetrix.com/reports/ehealthstar.com/m1hgD7fF
http://www.webpagetest.org/result/131015_84_PWG/

but is this worth to try?