Hi, Claudia!
Planning a first Walt Disney World vacation can be very fun, but very overwhelming! My best suggestion is to click
HERE. This guide will walk you through the entire planning process. You can enter your budget, travel dates, party size, and more, and the guide will give you suggestions as to what might work for you. Do this process several times until you get exactly the vacation of your dreams!
Another place to check is
HERE for Special Offers. You can get some really great deals to save money on your vacation. You can also call (407)W-DISNEY to speak to a Disney Reservationist. They are always very helpful with planning, and will make sure every detail is taken care of.
This might help a bit: My daughter is 12, and she loves Port Orleans French Quarter (moderate resort) and the Polynesian (deluxe resort). We usually go for 4 - 5 nights, and visit all 4 theme parks and Downtown Disney. Unless we are on an extended vacation or it is in the middle of summer, we usually skip the water parks.
Once you get some basic ideas, let us know if you have more planning questions. The Moms Panel is here to help! Have fun planning your first magical Walt Disney World vacation!