Stacked Dryer Repair

I replaced two separate switches in my kitchen with one dual switch. The top switch controls a light, the bottom a garbage disposal. These are on seperate breakers on my main box. I have four wires coming in: One Black (Hot) with multiple wires into one wire; one white (Hot?), two black (neutral). I tested this by using a voltage meter and found that the multiple black with either neutral registered 120v and the white with either neutral black registered 120v. I seem to have everything wired correctly: When the appropriate circuit breaker is off, the corresponding switch will not work. Here are my questions: 1) If the white wire IS hot, shouldn't it have be marked black? If yes, I can do this. 2) When I turn off the lower switch(disposal), a tiny blue flash appears within the switch. Is this normal, or have I done something wrong? (I did remove the the break off fin) Thanks Jeff

power went out for 5 hours the other day..now my stove wont work and some of my lights are dim...stove ligt and range lite work but do not heat up..also light in kitchen is dim..have reset all breakers...what gives?