Ok, I just got back from a (much longer) version of this. So, first, I will plug the trip report as I'm mostly done updating the "WDW -> DCL -> WDW" part (I'm stuck with real life eating up time for me to work on the Legoland update, then the rest of the posts will come rather quickly)...
Anyhow, so...shameless plug, here's my report.
http://forums.wdwmagic.com/threads/englanddgs-surf-and-turf-experience.870261/
So, if you want to skip all that (it's long, I don't blame you!)...here's my run down.
Yes. Yes, and YES!
I agree with @
Disneyfalcon , 4 and 4 is right (4 is gonna seem like a really short time on the ship!).
Just throwing it out there, I'd do it this way...
1 Day Arrive Evening, check into Disney Hotel, use ME from MCO
1 Day Magic Kingdom
1 Day EPCOT
Depart 4 day Cruise
1 Day Animal Kingdom
1 Day Hollywood Studios
.5 day at Magic Kingdom, fly home
If you are staying at a WDW Resort, DCL offers a bus service that will take you to Port Canaveral. It's $60 a person, as I recall. I found this a very relaxing way to get to the Cruise on my last trip.
Outside of the cost, there are advantages and disadvantages to using this service. I'm going off the top of my head, so if I get some of the exact details wrong, I'm sure someone will correct me...but...
Advantages
1) You will not have to pay for rental charges or parking (if you bring your own car) at the port. You also won't have to hassle with picking up or returning a rental.
2) If the bus, for whatever reason, is running late, I am TOLD (not sure how this actually works) that they will hold the ship for you. In any case, since you are on "Disney" transit, even if they don't hold the ship, I'm very sure you can twist their arm if the Bus broke down or got stuck in traffic...if you rent or otherwise arrange transportation, nope, can't do this.
3) You don't have to drive unfamiliar roads (not that it's that difficult a drive, it's not...but, it's still nice to kick back for that hour and a half commute and just let someone else do the driving)
Disadvantages
1) It will limit your mobility during your park stay (unless, you do like I did, and rent a car from the Car Care Center on property)
2) There is a cost ($60 a head, as I recall)...but when you look at rentals, you come close to that anyhow...so...
3) DCL will handle this transition beautifully...WDW will not (at least in my experience). I haven't written about that yet in my report, but I had a royal mess on my hands with ME the final day. Disney made it right, but it would have been a disaster had I not gotten involved a few nights before.
Other advice? Nothing at the moment...except...
YES YES YES! You'll love it!