unable to open moodle

Try this..

Go to your Safari menu bar click Safari > Preferences then select the General tab.

At the bottom of that pane make sure the box next to: Open "safe" files after downloading is selected.

See if that helped.

The link I am trying to open is on the school website itself.

Even if it worked before, the school network administrator may have a proxy setup as a filter to limit access to the site. You want to contact the school.

Please reply with the link you use to access the site.

Do you have the right version installed?

http://download.moodle.org/macosx/

Maybe the file is for a PC only. Why not contact Moodle for advice?

I didn't get an opportunity to edit my previous post.. sorry.

I just tried the .zip file here > http://download.moodle.org/

And it worked perfectly so that rules out a proxy.

Well, I can't access the site without a user name and password..

Did you check Safari > Preferences as I suggested previously?