If I were to install an SSD into the galileo 2 and a touch screen, would I be able to program it to let me choose an ISO to present to the USB client side of the board, and have a PC boot from it?
There aren't official tutorials about how to connect a SSD to a Galileo, are you going to connect it through USB or mPCIe? If you are talking about mPCIe be sure of the port you are going to use )
You can use a touch screen with the board, there is some information that may be helpful for you:
http://www.intel.com/content/dam/www/public/us/en/documents/white-papers/enabling-tft-lcd-display-ga... Enabling TFT LCD Display - Galileo Board
As you may know the Galileo doesn't have a GPU so you will need to use a screen that works with SPI, I2C or USB.
Do you want to be able to boot different images on the board using the same storage device (SD or SSD)?
If you use a SD card in the board; when you boot the board you can see the multiboot options, these options are located in the grub.conf file and you can add another image in order to be able to choose which image you are going to use. Is this what you're trying to do?
Please let us know if this is what you want to do.
I don't want to use the SDcard since it is limited to 32gig cards. I may use USB since movie SSDs are hard to find.
The idea is for the device to act like a USB boot disk. The touch screen would let me select what image to present to a PC attempting to boot off it.
Do you want to boot the Galileo board or do you want to boot an external PC?
In either way, you can change the image's files or create a custom image in order to be able to read the files from the SSD when the board is booting.
Check this thread: it may be helpful for you