I have been parent gov for 6 months and have just been asked to chair the Children&Learning Committee (ie curriculum, learning strategy, interventions, results, etc) EEEK! My mentor is the Chair, who has been brilliant and we talk to each other a lot; she's very good for sounding out ideas.
It is taking up biggish chunks of time: the week before a full meeting means a lot of reports being emailed, printed and read. School visits are really important but are mostly made during 9-3. Our full meetings are always 6.30 and the chair is ace at ensuring they are done by 8.30 and stopping things going off-track.
It's really interesting reading deeper into the stats around results and hearing the teachers explain in depth about them; I appreciate so much more their sheer professionalism and sense of duty towards our kids.
It is hard not to be judgemental about the school/head/teachers/parents but the most important quality I think a governor needs is diplomacy! Knowing you're there NOT to criticise teachers, but to ask questions and challenge why things are the way they are. A good school will have ready (and factually correct) answers to the challenges, a poor school will not and being challenged will hopefully help them to improve.
I would probably say that if you are in a family where both parents work FT, you might struggle to find the time to commit to governing, in addition to all the time that children need from you. Our governing board is only 12 people so each one is vital. Have a chat with your Chair to see what's expected. There might also be the option of being an Associate governor for, say, 6 months so that you can observe without commitment and then say yes or no to being as full governor. It's definitely not an easy job!