Please use </> code-tags to post your code.
int sensorValue1 = analogRead(A0);
int sensorValue2 = analogRead(A1);
int sensorValue3 = analogRead(A2);
int sensorValue4 = analogRead(A3);
int sensorValue5 = analogRead(A4);
int sensorValue6 = analogRead(A5);
normally one would use an array and a loop to read those values.
int voltage1 = sensorValue1 * (255.0 / 1023.0);
a simpler way would be
int voltage1 = sensorValue1 >> 2;
The 'runnig average' thing i am nor familiar with, but i would probably not even bother and rather just add an extra capacitor on the analog input.