Well, I know it is resistive, not capacitive, because, when it was "working", I could make it register a touch with any object and a little pressure.
No, I don't know what the 4 pins are, but I'm assuming that 2 of them are VCC and GND and the other two are X and Y data lines.
No, I don't know the operating voltage.
The image with the filename ending in 103946 is a photo of the touchscreen, the one ending in 103956 is the display and the ones ending in 104021 and 104042 are of the more complicated display connector.
EDIT: If it helps you in any way, the only numbers I could find on the touchscreen are "3622-T" (written on the glass) and "02 S530" (on a metal frame under the glass)