To answer the original question, Masons are simply a fraternity with a focus on behind the scenes charitable works. For example my lodge funds a woman's shelter and we also had a fundraiser to pay for three seeing eye dogs last year. There is no fanfare, just neighbor helping neighbor.
There is a close bond between Masons and that has been a cause for concern in the past since the ties from Lodge can influence a choice in contractor, roofer, insurance agent, etc prefering to do business with someone you know from Lodge rather than a non-Mason. However that is a personal choice and not something inforced.
The Shriners which at one time were made up of 32nd degree Masons was more of the public goodwill segment of the Masons. The Shriners circus and the little cars in parades are all used as means of raising money for the various Shriner burn units in place across North America (I can't speak to elsewhere). Now any 3rd degree mason is welcome to join the Shrine. This is because Masonry is dying off. It is mostly older men, long retired that make up the lodges.
The interest generated from National Treasure and the DaVinci Code have swelled the ranks slightly but Masonry of today is a pale shadow of its former self of the late 1600's to early 1900s. This is why you see so much Masonic references in American culture and even in the teaching of Russell. Masonic imagery was everywhere in North America during Russell's time, including most Adventist churches. So yes Russell used a prymid to help justify his chronology and to make predictions of the 'end times' that however did not make him a Mason, anymore than someone carrying an amercian dollar bill has masonic ties because of the 200 year old imagery contained on the currency.
There are rituals (aka lessons) that are involved with each degree of Masonry. Each degree teaches a different life lesson. The general motto of Masons is that we take good men and make them better. This is also why one's family and career take priority over Masonic activity. Masonry is intended to make someone a better husband and father not to take them away from their family. (Which was very refreshing approach considering the JW stance).
Inkling: Hope that gives you some basic information. Feel free to pm me if you have any other questions.