Okay, the first thing I will say.... Do not go inside the snack bar. Bring your own food and drink. It's a little scary. If you don't know what I mean then by all means check it out for yourself but don't say I didn't warn ya.
For drive-in movie theaters a thing of the past it is nice that there are a couple options out there still. The Scottsdale 6 is a good time out. You get exactly what you pay for, usually around $5 a person or so for two movies or three movies if you want to watch the first one again. It is a fun thing to do that is out of the ordinary. However I would warn against going if the temp outside is anywhere about 85 degreesish. Kinda miserable, unless you want to sit in your car with the AC running the whole time.
It's fun but I wouldn't tell ya to run right out tonight and go.