I'm afraid I didn't make myself clear, now that I read my posts.
The sync between iCal and Google Calendar works pretty well. I add my tasks on the iPad, and my Android syncs instantly. However, this doesn't work the other way, as I found out today. I still have to fix this.
But I still can't sync my PC so that it shows all my calendars that I installed in Google. Here I'd need some good advice.