geez - (I sure do talk to myself alot eh?) 
ok..well the IDE (both at home and at work) are running fine.. and as Mike pointed out.. using ISR does in fact result in that error (must be reserved key word for language..etc or something)
I would like get some feedback or discussion going
for best practice on implementing this code and optimizing it..
in the end there will be this sensor.. and two other ballbearing (swing/tilt) sensors that will need to be triggered to do something..
all (Im hoping) without much watch dogging by code (polling)..
but there are only 2 external interrupts I read.. (not sure what to do as a solution/approach for this)
however, in the final project these 'checks' will be constantly running/checking for the sensors/interrupts
for this example..I seem to be triggering 'multiple' interrupt routines with one flick..
Ive read about bounce/de-bouncing for switches...does this hold true for this type of sensor as well?
how would or should I handle this? each time there is a hit I want the 'tone/led' to play.. but I only want it to play 1 time on each hit..
however it seems that actually flicking can make the sensor make 'contact' a couple times...
how would I go about doing this with/in a timer? instead of the main loop? something that I can 'cycle' (like a timed loop or interval) through to check the flag/var being set?
I think if I could slow it down a bit I would really pick up the 'echo' contacts after the initial contact..
any suggestions or ideas?
thanks in advance. ;D