Hi Tara, and welcome (you and your son) to IceInSpace
,
The Skywatcher 8" Collapsible Dobsonian you mentioned is an ideal instrument (IMHO) for your needs.
It is portable, and because it is
collapsible (as apposed to breaking down into separate components) it does not cause the assembly problems Geoff mentioned earlier which are found in Lightbridge and similar
Truss Dobs. It is simplicity in itself to set up, and holds it collimation pretty well. (I have had two, a 10" and a 12"). You can be up and running in as little as 5 minutes.
And it is the best bang for buck of any telescope system.
And they hold their value fairly well if you come to sell it down the line.
To assist in locating and identifying celestial targets, I always recommend downloading the brilliant FREE Planetarium Software called Stellarium. at
http://stellarium.org/
Good luck with your purchasing decision.
And keep asking questions.