C182 pilot describes circumstances surrounding momentary loss of control during takeoff with an incorrect transponder setting.

Narrative

After receipt of my IFR clearance; I was interrupted by a passenger question while I was setting the transponder code. This caused the transponder to be set incorrectly. I failed to notice this error during the remainder of the preflight preparations. During the takeoff roll I looked down and saw the incorrect setting of the transponder and allowed myself to be distracted. I reached down to set the transponder. At that time the airplane veered right. Upon noticing the problem I corrected and completed the takeoff. I made several errors prior to the incident. The problems started with inattention during the preflight. I don't use chocks and I failed to notice that the FBO chocked the nose wheel. After starting and trying to taxi; I realized the problem and had to shut down and remove the chock. In receiving clearance to taxi; the Controller spoke so quickly that I had trouble understanding and had to ask for clarification twice. Further; the taxiway intersection signs were different than I am used to which left me confused as to how to complete my taxi clearance; which caused me to ask for clarification a third time. By this time I was a bit rattled and I missed checking the transponder in my final check. Adding insult to injury; when cleared to Departure Control; I set the correct frequency; but forgot to switch transmitters causing me to report on the Tower frequency. This caused the Controller to issue corrective instructions. The remainder to the trip went without incident.