Hi Tanya!
You didn't mention why you are planning on staying off-site. If it's due to budget concerns, you may want to research some of the special offers Disney is currently promoting - especially the
Buy 4 Get 3 Free offer. Another place I like to keep an eye out for discounts related to Disney is
mousesavers.com. This website will even post off-site deals which may also help you.
I am a strong believer of staying on-site - you can't beat the convenience. After flying in, you would be able to take advantage of Magical Express, possibly eliminating the need for a rental car. Once on-site, you'll be able to take advantage of Disney's transportation (bus, boat, monorail).
If you haven't already, I'd recommend ordering your
free Disney vacation planning DVD. This will help you regardless if you are staying on or off-site.
Assuming you have your off site accommodations made, you can purchase your tickets on
disneyworld.com. You can research Dining options
here and reservations can be made 90 days in advance (strongly recommended) by calling 407-WDW-DINE.
Unfortunately, we have limited space in our answers...I'd love to go on and on! After digesting the above, please send in any specific questions you have and we'll help you further!