HI there. Not knowing anything about your family, I am not sure what they would consider strange. I don't think any of it is strange. Some people do dress up in costume (called Cosplay since you have not been to conventions before) which is pretty standard for any MLP or Anime Con. That's about the most strange thing I can think of that a non-convention goer might think of.
The good thing about Babscon is that it's big but not too big. You will still get into the panels that you want to and the opportunity is there to meet the voice stars who do the characters on the show. There is dancing if you like to party late at night and also programs just for kids if some of your family is young. I don't know who is going to be there this year but in the past Nicole Oliver who voices Princess Celestia did a special story telling and if you were not a child or adult with a child you could not go to that one! I was very sad about that!
The hotel is laid out very well. There are ample elevators, a great food section that opens up with reasonably priced food during meal time and I have nothing bad to say about it. I might be on staff this year but the past 3 years I have not been and I think it's one of the nicest conventions I go to. I never really liked the events with 10,000 or more people. This is large enough to have the benefit of great celebrity appearances and programs without being too big to feel like you aren't getting to see or do anything.
Diva Pony's post in Is there anything strange at BABSCon? was marked as the answer