First, welcome to BHQ. I would say your in dire need of a top-end rebuild. If it is a 2003, and you bought it in 06' and it hasn't been touched, yeah I would say it's time! lol Rebuilding the carbs prolly wouldn't hurt. I think your having to start it on eather because you don't have enough compression in the cylinders to light off the fuel once the ignition hits. 100 isn't just plain terrible but as a reference stock compression should be somewhere around 120-130ish.
I could go on and on about this but putting it simple, go get ur top-end rebuilt. Check your reeds while you have it apart. Make sure they aren't cracked or broken. Once you get it put back together make DAMN sure you get your carbs synced properly. Go look at the site sponsors page and pick a builder. I've heard nothing but good things about all of them and I have personally dealt with F.A.S.T. and they are bad ass. Let us know what you decide.