Rewards programs award you "points" in exchange for clicking on banner ads, doing searches, shopping thru their portals and doing signups thru their sites. Some also send "paid" emails, which award more points when you click thru the link contained in the email.
The points that you earn can then be exchanged for prizes. Many prizes can be used to help defray the costs of a WDW vacation. Some of the better rewards would be Disney Dollars, Webcertificates and Supercertificates. GCs for
Walmart, Target, gasoline and phone cards are also some of the better rewards for WDW vacations.
In my opinion, some of the best programs are MyPoints, CreationsRewards, ClicktotheMagic, PCHPoints and LuckyPoints. They all send their rewards in a reasonable amount of time and have good customer service.
Some others have slow-to-pay reputations. Among them are Memolink, MileSource and ePoll. Those sites eventually pay but take months to do so. If you are going to WDW soon, don't waste your time on those programs.
Keep in mind that you are not getting something for nothing here. You will get a lot of SPAM as a result of doing rewards programs so it is a good idea to set up a separate email account for just rewards. You can get free email aacounts at Hotmail.com and Yahoo.com.
There are some great people on this board who know alot of ways to get the most out of each program. Read the stickies at the top of the board and don't be afraid to ask more questions.