You could write it like this:

pctin((q1 >= 1 and q1 <=5) or q2==2, true)

Or you could use the inrange function:

pctin(inrange(q1,1,5) or q2==2, true)  

You're basically saying: compute the percent of records where ((q1 is within 1 and 5) or (q2 equals 2)) is true.