My Suzuki WagonR (2008) is about four years old now. The problem is that my car refuses to start sometimes. I doubt my battery is the problem and the history of my battery is that I have not changed my battery from the day of purchase, except adding some distilled water. But still I have no problems operating my music system or lighting the headlights without starting the engine, which makes me feel that the problem lies with the starter itself. Again most of the time the car refuses to start after lighting the headlamps. What might be the problem?
The first thing you should try is replacing the battery completely, contrary to what you're guessing. Whether or not you can turn on your headlights or turn on your radio has little bearing on the health of your battery and whether it can start the engine.
The fact that you haven't ever replaced the battery since buying the car in 2008 and now the car is having trouble starting sometimes is a dead giveaway. The average battery goes strong for about 4 years.