I need help . my iCal has a lot of listing on the left column of calendar labels . some of my own doing, some of some apps that I installed then uninstalled.

recently, 10.6 created an exchange calendar , i added some label to that too

the bottom line is this:
1.If i delete all lables both on the ical and on mobilem.com account what will I end up with? just the exchange calendar?
2. I have spanning sync installed , it allwed me to use google calendar and sync it to my iphone and ical. that was before 10.6 and the compatibility with MS exchange. now that we have it I am thinking of getting rid of it to avoid duplicate events on my iphone and ical.?

Thanks for helping