When you are a guest at any WDW owned-and-operated resort, you enjoy full use of all WDW transportation. In addition, you don't have to pay to park at the resorts OR at any of the parks. The only differences between Value and Moderate and Deluxe resorts begin and end within the resorts themselves (such as the size of the room and the amenities the resort has). But every guest in every resort has the same basic rights and privileges.
If you buy something at a park and want it shipped to your resort, it gets shipped to your resort's gift shop, and you pick it up there ... they don't deliver to your room. Keep in mind that this delivery usually is set up for the next day. Another type of delivery is you can have your purchase waiting for you near the park exit ... in other words, you can buy it early in the day and then not have to lug it around with you through the park; however, there are time limits to this, such as it takes a few hours, and if you will be leaving the park soon you won't be able to use it.
About tickets ....
When you buy tickets, you aren't buying "admissions," you're buying "days." Unless you buy the Park Hopper option, you aren't permitted to enter two theme parks on the same day. After Day 4, the price of each additional day is only about $2 ... the price difference between a 4-day ticket and a 10-day ticket is only about $14 total.
If you try to use a non-hopper ticket in two parks in a single day, when you get to the second park the turnstile will not unlock, and the greeter on the other side will see a display which will inform him/her why you were denied admission.
I strongly disagree that it's always a good idea to buy a 10-day ticket with no expiration. A lot of times, doing this WASTES hundreds of dollars. This option only makes sense when the 10-day non-expiring ticket TOTALLY covers you park needs for two or more trips. If you have to add even one little park day for your second trip, then you've wasted hundreds of dollars as compared with buying separate tickets for separate trips. I can provide the math upon request.