Question about Slideshow invisibles trivia.

I'm looking for feedback from anyone who reads this who actually goes to Western Film to see movies. Before the movie starts we play a PowerPoint slide show with trivia. Some of the trivia I get from imdb which is usually more in the form of 'did you know...' rather than questions. The visual trivia I get from a site called filmwise.com (with permission) I started using their invisibles trivia as they seemed neat and they make a lot of them so I had lots to choose from. In the invisibles trivia they take a scene from a movie and someone very skillfully erases the humans leaving only their clothing and sets. You then have to guess what the film is.

I like using the invisibles for the slideshow because they are easy to change which takes less time so I can change the slide show more often. However I'm not sure how effective they are. I have to make the images larger for the slide show which reduces resolution and then the image gets even bigger on the big screen.

So I have a few questions.

Do people have trouble making out what the image is because it's too fuzzy sometimes?

Are they too hard?

Is having trivia before a movie tacky?

I make sure the trivia isn't so easy as to be almost insulting as I've seen at other theatres.

I just updated the slide show. This time I tried to pick invisibles that were more clear visually. I also tried to pick ones that were a little easier than some in the past.

If anyone checks it out let me know what you think.

P.S. if you are a movie buff you might want to check out the invisibles at the site. I'm surprised how many people get all 8 each week. I can usually get about half.