I first started going to anime cons at Kumoricon 2009. I pre-registered and the line went through MUCH faster than the registration (from what I saw, registration was LOONG. Pre-registration was that long, but went by faster), so I recommend pre-registering before the deadline (August 15th)
Going to anime cons at a certain time depends. People usually go early in the morning on the first day, so they're guaranteed to get their badge, but I usually get there a half hour to an hour after Will-Call/Pre-Registration is open, when the line isn't AS long as it is in the morning. Or, on Day 0, you can pick up your badge, then go about your day the next day without worries. I usually don't, since it saves us a day at a hotel (we try to get the best hotel that is affordable and great)
Also, MOST anime conventions (like Kumoricon! c: ) post an online schedule before the con starts, so you will be able to plan before-hand on what events/panels you want to attend. I always pay attention to the forum/site updates that will effect the convention, like guest updates, schedule updates, times, etc.
