We have twice done a disney land and sea vacation. They were both awesome. We just got back this past weekend from our 2nd trip and for this one, we did drive down and back. Disney no longer offers the package "Land and Sea", so now you book both separately but there are benefits to this! If there are any specials such as free dining, you can now take advantage of it whereas before you could not of. The cruise was fabulous, but we wont' do a 4 day cruise again. Instead we'll do longer cruises.
Although WDW was great, it just did not hold the Magic and Wonder for me this time around. Two of my kids were miserable at times, and my two younger ones just told me when they were asked "which would you choose if you could only do one,,,,, WDW or a
Disney Cruise next year?" Both of them shouted "CRUISE!" I'm Glad we did the land and sea though, but I think we've had our WDW fix for a while now. Perhaps if we go without our teenagers next time and just take the younger two, I'd have a much more pleasant experience.
As far as best time of year to go. Fall would be the better value for you dollar (but not during holiday times like U.S. thanksgiving) Spring would be the next best choice. You need to watch out for deals and book then, unless you just can't hold out for a deal that might never turn up. This fall, Disney had free dining, next spring Disney has Kids sail free on 3 and 4 night cruises. There's no gurantee Disney will offer those again (though the free dining in the fall has run for a few years at least now). We did a combined land and sea vacation (4 park days and 4 sea nights) for 6 people (3 adults as one of my children are 18 now, and 3 children) with
trip insurance and the dining plan for just over $7000.00. I know that could have been booked cheaper if both parts had been booked separately. We could have taken advantage of free dining, we could have stayed in a value resort instead of moderate ect.... lots of ways to have reduced that cost (only in retrospect)
We have now found a 7 night Western Caribbean cruise for two adults and 2 children for just over $3000.00, and we are going for it. We'll fly next time though. (drive to SYR though as flying out of Ottawa costs a fortune itself)
If you have any other questions, I'd be happy to help you with them.