You are kidding yourself if you think that you are not going to be standing in long lines. There are 1 million AP holders and they are all going to want to go when you are there. 2 reasons... Star and Tours! It's going to reopen on the 10th. It should draw some decent crowds. Also little mermaid should be opening in May sometime too but that is still a crap shoot. Now, while you are there, it is still considered the off season, so while there may be fewer crowds, the lines will still be long, why? Because in the off season they don't staff the rides at full capacity. They may only open one side of the Matterhorn, they may only run one elevator in haunted mansion, one ramp of boats in small world, and maybe only 2 lanes of cars in autopia etc.. etc.. Not to mention refurbs happen in the off season so rides will be down, I think Splash will still be down when you are there.

You should check out these to articles by Hydroguy to get a better understanding of what to expect:
What You Should Know About Off-Season at DLR
http://www.disboards.com/showthread.php?p=18462889
Understanding AP Blockouts and Impact on Crowds
http://www.disboards.com/showthread.php?t=2365983
We arrive the Friday before Memorial Day weekend, but since that's the beginning of the summer season everything should be running at full steam so it shouldn't be too bad. We expect crowds, but if it gets crazy well just head back to the hotel and hang out in the pool. Infact, I plan on reserving a cabanna for the weekend so I can watch the Indy 500 while the kiddos swim.
Have Fun!