Virginia,
Great to hear from you again! Let's plan a step at a time focusing on your DS. Deciding when to visit is the 1st step. Generally, peak seasons are around all major holidays. Anytime there are major events planned (Disney Marathon held in early Jan. & the Food & Wine Festival set for Oct 1st - Nov 14th, 2010), spring break (mid-March to mid-April), summer months (June - mid Aug) & the wk b/t Christmas & New Years will be super crowded.
Its usually least crowded the 2nd wk of Jan - 1st wk of Feb (except the Marathon wkend), just after Labor Day until Food & Wine Festival begins; wk after Food & Wine Festival until wk of Thanksgiving & wk after Thanksgiving thru wk b/f Christmas.
Typically, the hottest months to visit are June - Sept. June - Sept are also generally the wettest months. If your DS is sensitive to heat, avoid the summer months.
If possible, stay on property. In addition to the park perks (EMH, complimentary airport transportation, resort transportation, Disney Dining Plan) it will make it easier for you to go back to your resort for a break.
Check the WDW website for specials on vacation pkgs or speak w/ a travel agent. If you have a Chase Disney Rewards Visa, check on their pkgs & AAA if you're a member. Look at
www.mousesavers.com - their website has great info on $ saving tips.
Because you frequent Disneyland, you may want to look into the
Disney Premier Passport which will allow you unlimited visits to both Disneyland Resorts & all of the Resorts at WDW (see link for complete details). Out of room again. Let me know the ages of your travel party & we can talk about where to start in the parks & which parks to attend.