We stayed last Easter off site at Emerald Island Resort. We drove to all the parks. We didn't have any problems with parking/traffic.
...but...
We arrived at the parks in time for rope drop which meant getting up early (sometimes getting up at 6am to be at the parks in time). We left the parks around 2-3pm when they were getting too busy to really be fun. (I don't enjoy waiting in long lines on a hot day). I really cannot stress enough - get to the parks early.
We use TGM's advise on which park to go to and getting around the park to do all the best attractions. At the end of the day we had a great, unstressful visit to the parks. Saw all the major attractions, left the parks early, went back to the home and swam.
No, we didn't do everything, but we did the best of everything. (Got a few 'dreams' amongst us all too!)
We had a group of 14 of us ranging from 1 year old to 50. We did split up so the 'roller coaster faatics' could do those whilst the younger ones could do more age appropriate rides.
We did book lunch in the restaurants, but we did it mostly by phoning up the night before (because we were being flexible in which park we would do when). We managed to get reservations for our group of 14 with not much hassle. We were flexible about where we went and often we were sitting down for lunch at 11.00 - 11.30 am (which worked out fine - trust me! After an early start, early lunch is great and well needed!).
We went back to MGM for fantasmic one evening (had fantasmic reservations already booked in advance) and saw the EPCOT fireworks from one of the cruise boats another night (great view - highly recommend it!).
Enjoy it! We did (and I was totally worried about going over Easter as I was used to going out of season!)
-Kay