This is the first time a Freedom Friday has games that I want to try. My only issue is that it seems like I have to install the Desura client to download the games. I am not totally anti client has I have Steam but would like to know how invasive Desura is. Do I need it running in order to play Desura games?
You don't need the client to install or play the games.
You can add them to your collection from the front page - search for the title, then click on "Add to my collection".
On the game page click on "Install game" and then choose "other options" (or something along these lines). This will take you to a screen were you can download the installers directly and then run them to install the games, and then... play! :-)