No problem, and feel free to post here whenever you have a problem you can't figure out yourself... there are plenty of people willing to help.
There are quite a few sites on learning Linux out there, but one I've found pretty helpful in understanding how the system itself works (not just whatever GUI is on top of it), is http://www.slackbook.org/
. It's written for Slackware but should be mostly appropriate for whatever distribution you use.
As for the bash script, a quick search on http://www.google.com/linux
for "bash script" will give you more resources than you'll have time to read. Basically, to make a script like that, you make the first line "#!/bin/bash" which tells the system to use the bash interpreter to process whatever you write below. At that point, you can type whatever lines you want executed after that in the file, exactly the same as you'd type them on the command line. Then you just have to make the file executable so you can run it.
One more thing: you usually have to be root to mount filesystems. Take a look at "sudo" if you want to let any user be able to do that without changing to root just to mount the cdrom.