A good place to start is by clicking the Rent/Trade FAQ's near the top of this page.
Also, decide which
DVC resort where you would be interested in staying--OKW,BWV,BCV or WVL--and what size accommodation--studio,one or two bedroom, or grand villas, which accommodate respectively 4 people, 4 people, 8 people and 12 people--and the time of year you are considering travelling.
The time of year, size of accommodation, resort and view determine the number of points required for your stay. Fri-Sat nights require significantly more points than Sun-Thurs. Holidays are also higher point values.
This is just a brief overview for you to begin. You might find some links here as many, including Doc, have posted some great photos of the accommodations and you might also access info from the disneyworld website under "home-away-from-home resorts."