Hello Heather! As long as you aren't trying to find reservations for popular restaurants at the last minute, I think the system is very reliable and easy to use. You start by visiting the
restaurant page on disneyworld.com. You'll notice there are filters on the left side of the page that can help you narrow down your search.
Once you find a restaurant you want to book, click on the 'book a reservation' link. You'll notice when you try to book your first reservation, there is a link to 'retrieve your reservation.' You'll want to click this first to enter your resort reservation information which will allow you to book reservations for your check-in day, plus 10 additional days (assuming you are making reservations exactly 90* days prior to your check in).
Next, you can enter the date you want to dine at this restaurant or if you have flexibility, click on the date range box which will allow the system to search several days at once. Enter your desired time (note: the system will search within 2 hours from the time you enter) and the number of people in your party.
Once the system returns back the results, you can select the desired reservation time by clicking on the radio button to the left of the desired time. Then at the bottom of the page, click 'add to cart' after you've entered the security check words. You can continue this process to make other dining reservations and when you are ready to check-out, just follow the steps on the screen. You will receive a confirmation email within minutes.
Most restaurants do not require a credit card but if you have a reservation that does, you can simply enter it when prompted.
Good luck! Diane :)
* Note: on October 27, 2009, Disney will be expanding it's advanced dining window to 180 days.