If you try to haul it on fixed without pedal attachment and you're not used to it, you will meat tenderize your legs sooner or later. This hurts. A lot. Can be gory too.

Brake pads should be as close to the rim as you can get them without them rubbing when you pedal hard and the wheel deflects a bit. Don't go by the quick releases, with the brakes dialed in it may rub a little even with them open. Also, many road brakes don't have a reach adjustment, so people with small hands may run the brake a little more open so that they can get a stronger, more closed grip on the brake.