First, i think the bigger the tank for a newb the better. i am not saying you personally, but newbs like to be a bit lax and don't do all things as they should, meaning waterchanges, top off, parameter checks ect. in small tanks like a 30g- things change really fast and can kill somthing in the tank just as fast (ie SG, if you don't top off but once a week SG goes up sky high and it can kill corals anemones). now that that's said...
Congrats, i can't wait to get my big tank, have to talk the Mrs. into it first. anywho, ditch the canister filter and yes a skimmer is the best. the more you spend on a skimmer the better it works (you get what you paid for) brands are many i'd say look at www.marinedepot.com
and read reviews or ask us online, we are more than happy to help. Skimmer should go into sump which is best(cheeper) if you DYI. Also look into a refugium which works well with corals and many types of fish (see Reefkeeping 101 – Sumps! by Marc Levenson - Reefkeeping.com
Lighting is very important. If you want an anemone or hard corals like SPS, then i'd say get Metal Haylides (MH) or T5. the rule of thumb is you want 7-8watts per gallon. so you have 100g you need 700-800watts too keep everything alive and kicking. I think getting the retrofit is the cheapest way of doing it otherwise you'll be spending more than you want to. t5 has become more and more popular because it's cheaper than MH and changing up lighting is easier than if you were to use MH because of reasons that will be explained in later threads if you're interested (or you can PM me).
Flow is the other big factor you need at least 10-20 times your tank size so you have 100g then you'll need 1000-2000gph (gallons per hour) worth of flow if not you'll find many dead spots in your tank and stuff you don't want will grow. the more random you can get your flow the better your coral will grow and enjoy it. and if you think this is too big of a project for you mail it to me and i'll find something to do with it
One last thing. Live Rock (LR) is good filtration and when you are cycling use only one piece of uncured (otherwise your tank will give off a horrible smell) and you want sand NOT
crushed coral or big subrtrates at the bottom of the tank. For LR you generally want about 2lbs per gallon, but many go less or more (to each his own).
Please ask away with anything you may want to know.