Here are some prices to compare:
7 day Park Hopper PLUS: $305 from Florida Orlando Tickets
7 day Park Hopper PLUS: $326 advance purch from WDW
(Includes 7 days at main parks and 4 PLUS visits)
Park Hopper days and PLUS options never expire, meaning that if you decide not to visit a park on any given day, get sick, etc., you can keep the ticket for your next trip. This is the most popular way to go.
7day/6night Unlimited Park Hopper: $333 advance from WDW
(Unlimited admission to all WDW attractions. 10% disc if DVC member)
You must stay at a WDW hotel to get the UPH. You get unlimited access to all parks and attractions, but that access ends at midnight of the day your trip ends. This pass is typically only recommended if you really are going to use it to its fullest, including visits to the water parks, Disney Quest, Pleasure Island, etc. Otherwise the PHP is more economical.
If you're planning another Disney visit in the next 365 days, an Annual Pass is the way to go:
Annual Pass (4 main parks only): $392
Premium Annual Pass (all WDW attractions): $520