Your ISR stops because it tries to print. NEVER print from within an interrupt, because printing depends on interrupts and those are turned off in an ISR.
ISRs should be as short as possible. Yours is way, way too long. Take almost everything out of the ISR and put it in the main loop.
The ISR should collect and store the absolute minimum data necessary, set a global flag (declared "volatile") that the data need to be processed, and exit.