When visiting Orlando, you need to find an excellent way to travel around in order to take in the sights and sounds of the city. However, you only have a few available transportation options available to you that are actually going to work. Due to this, you need to think about what all you want to see, where you are going to be staying and what works for your budget and go from there. All of that is going to be extremely important in determining the form of transportation you need to consider for your trip.
In all honesty, you probably need to rent a car. Unless you stay in one of the Disney theme park hotels and don't plan on going anywhere else but Disney World, you need to rent a car. There is so much to see and do around Orlando, from Disney World to Universal Studios, Sea World (if that is your thing) and different attractions, all of which are spread apart form one another. Due to this, the only true method for arriving at the different parks is to rent a car. The city is just so spread out that there is no excellent form of transportation to get to one place to another.
A hotel shuttle is possible, depending on where you want to go. Many hotels do provide shuttles to the amusement parks, but you have to wait on everyone else in the hotel to leave, and it is also going to take much longer to get to the park as well. When you are spending a few hundred dollars a day on the parks (when you have a family), using a hotel shuttle might not be cost efficient, which means renting a car is just going to be better for the entire trip.
Of course, if you are staying in one of the Disney theme park hotels and you don't plan on venturing to a differnt location outside Disney World, the monorail system is an excellent option for you. This monorail departs straight from your hotel and takes you to the parks, so you really don't have to worry about anything else in terms of transportation. If you are visiting Disney and want to do it up right, you might as well stay inside one of their hotels. There are some over the top Disney hotels, but there are also others that offer some incredible amenities. Plus, you can see Mickey before you make it to the park with your kids and get it out of the way. That way there is one less character you have to stand in line with for pictures and their autograph.
When visiting Orlando, there are only a few transportation options available to you. Ultimately, you really need to think about where you are staying and what you want to see and do, as this plays the largest role in what you are actually going to use as your primary means of transportation and for arriving at the best sights.