[Warik]

1. I didn't look at the list. I'll just tell you what has worked for me over the years.

Crunches. Crunches are *the absolute best* exercise for training your upper abs. Crunches on exercise ball are better.
Do not waste your time with situps. Situps do more work on the hip flexors than anything else.

Other great ones are leg raises (lay flat on your back, hands under your butt, legs straight out and raise to about a 45 degree angle and bring back down - don't touch the floor), and hanging knee raises (hang from a pull up bar, bring your knees up, lower them down, repeat).

Why such a small list of exercises? Because you don't need to know 10 or 20. Why? Because...

2. Yes, you do need rest days, and most people who train their abs train them wrong. You don't need to do 100 crunches every day to get a 6-pack. In fact, doing 100 crunches every day is the reason most people don't have decent abs. The abdominals are a muscle just like your biceps, quadriceps, pecs, etc... They are composed mostly of fast-twitch muscle fibers - which means they respond better to low repetition weight training as opposed to high volume work. The lower abs have a little more slow-twitch in them than the upper abs and do respond better to a few more reps, but certainly not in the 100s.

Here are my suggestions:

Pick two days a week to train abs, space them out so you get maximum rest between them. Examples: Monday & Thursday, Tuesday & Friday, etc... Do 3 sets of 10 crunches and 3 sets of 12 lying leg raises. Do them with a smooth tempo and focus on doing them *perfectly*. Rest 2 minutes between each set.

When you are able to do all 3 sets with perfect form, start adding weight. For the crunches put a dumbbell or weight plate on your chest or behind your head. Keep working till you do them perfectly and then move up. For the leg raises, hold a dumbbell between your feet.

This will hurt the next day the first few times more than doing a bunch of sit ups ever did.

Note that this alone will not give you a well-defined stomach. You can do this for 20 years and if you don't have low bodyfat, you won't see a thing (but anyone who punches you in the stomach will regret it because under that fat you'll have a solid wall of abs).

However... my bodyfat is naturally low due to my metabolism, so I am completely useless if you need info on that. Hop on a treadmill or something I guess.