Hello, Peggy!
Taking your grandchildren at ages 4 and 6 is a fabulous idea! What fun you'll all have! (And their first visit, too? Woo hoo!)
There are several options you have when selecting your resort, so begin by visiting
Walt Disney World's website, where you can "shop" for prices right then and there. You'll get a better idea of prices based on time of year, day of the week, if any holidays are nearby as well as the type of accommodations selected.
Disney's new Art of Animation Resort is a wonderful
Value Resort which includes fantastic Disney theming your whole group will love. This resort, along with Disney's All-Star Music Resort, offer Family Suites in addition to standard rooms, which also give you a little more space, an extra bathroom and even a mini-kitchen (especially great for early morning breakfasts in the room!)
Moderate Resorts offer a little extra luxury, a slide at the main pool and some additional dining options.
Deluxe Resorts are often the most convenient of the resorts, as they are often located a bit closer to at least one park.
Pick the time frame for your trip on the link above, select accommodations to get a rough idea of cost. You'll find one is comfortable for you, then we can narrow down the choices that fall within that range.
No matter what, it's a win-win situation; all of the Walt Disney World Resorts have fabulous features and incredible perks that you simply cannot find elsewhere.
Send more questions as you think of them! I'd love to help you plan this very special trip to WDW!