Jess - a really good starting point is allearsnet.com It has tons of info to get you started. Also, the disney website itself is a great starting point ot find out about the World.
This chatboard is one of the best I've found to answer any buring questions you have or confusion you encounter.
But sometimes if you ask us, you may get as many different answers.
Probably your most important starting point is to think about when you want to go to WDW. The above page has info on Orlando weather.
Second is to consider your general budget.
Third, once you've begun to figure out what you can afford, look at what you'll get for waht you'll pay. You could stay at a top end resort suite for over $3000 a night, eat very well, and spend over $5000 on a two day trip (I could certainly find a way to spend that much if I was forced )- or you can stay for a week at a value resort with base tickets, and basic dining for about $1600 (not counting transportation to Orlando). And there are a thousand choices in between the two extremes!
When you start talking budget, this page (WDWinfo) has great info, and so does a page called mousesavers.
Once you get through that, decide how you want to get to the Orlando area - drive or fly. I suppose you could also walk, take atrain, or bus - but most people choose the first two. MCO is, in my opinion, a pretty nice airport.
Another consideration to make a long the way is wether to stay at a resort on Disney property or choose an offsite hotel. The three webpages above can help you determine which will be best for you. Either can be a good choice. I prefer onsite, but lot sof other experienced folks like staying offsite. Once you are onsite, you can use all Disney transportation. Offsite you'll need to drive back and forth. Onsite also gives you extra perks.
Once you know where, when, and how...then you can dissect the fun stuff. Basically, you'lll want to see all four Disney parks and you'll need at least a day to see each park. Six days is a good touring time. It will allow you so visit each park, and give you two days to go back to your favorites, use the pool at your resort, maybe shop at downtown Disney, or just sleep in.
You can also start to think about your dining choices. If you want to eat at all quickservice places, then you don't have to make any dining reservations, you'll have quite a few options to choose from (even Japanese and Moroccan food!), you'll eat meals quickly, and you'll eat on the lowest budget. But you'll be missing out on some fun dining choices, and though there are some healthy options in QS - most TS locations offer some higher quality ingredients.
Maybe you want to have some groceries?
On the other hand, Disney has some moderate eateries, and some very high end restaurants as well. Most have great atmosphere, but if you want finer dining, then you'll probably want to look at menus, and you'll have to call for reservations. Disney places take reservations at 180 days, and the most popular places fill up fast. At 90 days you'll still be able to get some very good choices most of the year, but as your dates draw closer your table service choices will become more limited (in terms of being able to get a reservation).
I suggest at MOST one TS location per day, and QS the rest of the day. Too many TS means you spend all your time trying to get to restaurants - and not enough time on attractions. WDW is a BIG place and it can take a whilet o get from one place to another.
You'll also want to picka park ticket. Probably for a first trip a base ticket is fine. Yuo may want consider park hopping, but you won't need the no expire option, and probablythe waterpark option is more than you need. There is more than enoughin the regular parks to keep a family occupied for more thana full day. If you spend a week in WDW, with just a base ticket, you'll see most ofthe four major parks, but even if you spent a month in WDW , you probably would get to see EVERYTHING WDW hs to offer. That's part of what makes it fun!
Once you ahve all that, be certain to read up about fastpass, and understand how those work before you go. DIS can answer all your questions about good fastpass strategies.
Last, don't stress. Dont try to do every possible thing there is to do at WDW. On your first trip, there will be plenty to see and do, and you'll have the means to see and do most of it. If there's one micstake I seetime and again here, it's first timers trying to fit every little thing in to their first trip. See the parades, see the fireworks, go on as many rides as you can...don't drive yourself crazy booking reservations for more than one meal a day, don't try to book special packages, don't try to see every detail of every nook of WDW.