well your flights are going to be at least £1300, probably more
your car and/or car insurance about £300
So, presuming you have already covered misc costs, like car parking, transfers, etc, you have about £1000 for your hotel for week
At disney for about a grand you could get
Disneys Port Orleans French Quarter or Riverside
Disney's Carribbean Beach Both are much better than the value resrts, and the Port Orleans Riverside I think is really nice - but they are hotels, so you won't have the space like a villa.
You could get a nicer disney hotel - such as Wilderness lodge or Animal Kindom lodge for about £1500. But again, they are still just rooms, and not villas, so still not gonna hit the spot if you are used to or like villa type space
To get a Disney Villa (such as Saratoga Springs or or Old Key West) that will cost about £1600/1700. Disney Villas are nice, but again not quite as big or as well appointed as off site villas, but you do get the 'Disney benefits' if that floats your boat. (personally never quite sure they are worth the extra cash, and although we love Disney, its nice to get a break from it at a 'non Disneyfied' resort)
The most luxurious hotels (like Polynesian) will be about £2000.
If you buy your tickets to Disney with any of the above, you may be lucky enough to get free dining - then you might consider its worth it.
You would also get your transfer from the airport and could get your hire car delivered to your hotel, or perhaps consider doing without a car at all and using disney transport. They may even do your transfer (including your luggage to Port Canaveral for your cruise.
However, if you are not doing Disney parks for the entire week before your cruise (eg, if you are going to other parks such as Se World, or Wizarding World at Island of Adventure) then the extra you will pay for staying at Disney for a week most certainily will not be worth it.
You will then be better off with a nice luxury villa resort such as Sheraton Vistana Villages, which for a week you could get a two bedrrom villa, full kitchen, two bathrooms, living and dining areas, daily housekeeping for around £900. We have stayed here twice, and reccomend it highly.
This kind of resort is a 15 minute drive to the disney parks and downtown disney, is super child friendly, with 3 separate luxury pools with waterfalls, daily activities, shop, restaurant, hammocks in trees, play parks, outdoor BBQ stations, lovely grounds, free secure parking, security manned entry gate, etc
This resort we have stayed at twice (also with two children similar age) It has an International Drive address, but is nowhere near the main part of International Drive, and is in the quiter Lake Buena Vista area.
Sheraton Vistana Villages is nicer (in my opintion) to the similarly named sister resort of Sheraton Vistana Resort, so keep an eye out as they often get mixed up. Check out trip advisor for reviews (byt mke sure you search Vistana Villages and not the larger Vistana resort)
Below are a selection of real life pictures to this resort from our last visit
Plus here is the official site link
Sheraton Vistana Villages, 12401 International Drive
Orlando, FL 32821
Other similar resorts you should consider are Floridays, Fountains Resort, and maybe Hilton Bonnet Creek - just search for them on Google or trip advisor