colleen wrote:.... you could run 2 videos independently from one RPi.
that would be perfect. How can I do that?[/quote]
Attached is a photo, shrunk to fit the forum's file size limit, of 2 of my (different makes, sizes, etc.) screens, attached to a single RPi3, so HDMI on 1, VGA on the other, displaying a H264 file (not generated by me, but handy for testing). Many projectors have VGA input as well as HDMI but if only HDMI input available, a VGA to HDMI adapter works fine. It's the same file played through 2 different interfaces to highlight synchronisation. Obviously in practice you'd have 2 different files.
A sticky thread, a few posts up from yours:
viewtopic.php?f=91&t=94424&sid=a49efcf1 ... bfba4e10a3
gives you lots of details.
I used this setup over a year ago at a Cheltenham RPi meeting demonstrating different graphics files running simultaneously on 2 big screens, where they had excellent large screen Philips monitors, & it was hard to decide which was showing VGA or HDMI.
Only you can decide if the quality, degree of synchronisation, etc. is adequate for your needs, (which is why I asked if you had anything publicly available). It's probably worth getting one of the kits though, if only to show you its possibilities in your art projects. The DPI/vga666 interface can be extended to 8 bits per colour, & a pcb for such is available from a forum contributor. ISTR a ready made board (not the same as in the thread above) is available from an Asian supplier.
As you can imagine, it's somewhat easier to achieve better synch' if everything emanates from one RPi.
I am too, making a possibly rash assumption here that you don't need (synch'd) audio to each of your two h264 videos?
The program used to display h264 files, is actually included in the Raspbian OS µSD card example source files:
A small modification to allow looping files is described in a forum post somewhere in the multimedia sub-forum. It displays only h264 files, not audio. You can of course have a "sound track" playing from an amplifier connected to RPi's audio output which is independent of the 2 videos.
Good luck with your show.