1. Parks will be open late because it is still the holiday season.
2. Don't know about ride closures yet, but you can keep tabs on that - at least, the planned ride closures - on the DL website. Any sudden ride malfunctions remain to be seen.
3. The crowds will be RIDICULOUS. The weekend between Christmas and New Year's is the busiest time of the whole year, and having been there on New Year's Eve myself, I can attest to that. I mean, wall to wall people. Scary crowds, sometimes not moving at all. It is a time of year when most people on this board say they would NEVER go. However, you will be there several days, so after New Year's is when you will likely get the most done. As soon a January 1 passes, everyone goes home. But be prepared. The park often reaches capacity during that time. I recommend taking whatever oppportunity to visit DLR during the holidays and getting to see all the fun holiday decorations and rides and food and all that, so you will get that, but you will also get a WHOLE LOT OF PEOPLE along with it!!
Imagine the absolute maximum amount of people you think can fit on Main Street, shoulder to shoulder, front to back. Then add about 200 more in any slightly unoccupied spot.
I think you get the idea.
You will think to yourself, "It can't be as bad at they say it is. Let's do it!" The next day you will think, "Wow, it was even more crowded than they said."
Been there. Done that. Can honestly tell you as one of the biggest Disneyland fans you will ever meet, will never do it again.
My advice. Don't plan to park hop during the day. Pick your park and stay there. With the expected crowds you might not be allowed back into DL or DCA if they are at capacity.
DL usually only puts park hours out 2-3 months ahead of time. January hours will probably go up in October after Disney finishes its fiscal year end crunch.
As others have mentioned, Disneyland is extremely crowded on NYE. When we went in 1998, we were really excited because the park was open until 2:00am. We watched the fireworks from near the Partners statue. The place was so crowded that they actually opened up the backstage area behind Main Street to help people exit the park and even then we didn't make it out until 1:30am or so.
In 2004, my family went to DCA on NYE and found the park empty. I opted to watch the fireworks from near the castle and had to wait about 4 hours.
So if I changed my dates to Jan 2nd-6th (5-day park hopper), I should have relatively no waiting times anywhere, christmas decorations still up, no ride closures, and decent park hours, even though these dates run through a weekend?
If you look under "events" at the DLR website it says the holiday season runs through Jan 4th. I take that to mean that on the 5th some rides will be closed to take down decorations.
I'm going on the 2nd and wanted to check the hours but have to wait.
So if I changed my dates to Jan 2nd-6th (5-day park hopper), I should have relatively no waiting times anywhere, christmas decorations still up, no ride closures, and decent park hours, even though these dates run through a weekend?
I think that once you get past January 1, the crowds will thin up quite a bit. Even though some kids are still off school, many parents have to get back to work. It is really just the week between Christmas and right up through New Year's that is CRAZY SCARY HORRIBLE. Disneyland is always crowded in some way, so there is no avoiding that. But if seeing holiday decorations and riding Haunted Mansion Holiday and Small World Holiday, and seeing some of the other special holiday stuff and eating holiday treats, is part of the goal of your trip, then you would have January 2nd, 3rd and probably the 4th to really enjoy that stuff with fewer crowds. Even January 1st is not SO bad in the morning, as many people are asleep in their hotels from staying up late the night before. We noticed that early New Year's Day was not so bad when we went, but around noon the crowds started pouring in! So you might be able to get in some good ride time in the morning of January 1, but otherwise January 2nd and beyond is your best bet for still catching the holiday magic and not getting trampled or squished in the process!
So if I changed my dates to Jan 2nd-6th (5-day park hopper), I should have relatively no waiting times anywhere, christmas decorations still up, no ride closures, and decent park hours, even though these dates run through a weekend?
What I have always found to be true is, if it is a good time for you and your family to go because of timing/schedule issues especially with kid's school schedules, then you can expect it is also a good time for everyone else to go as well and the parks will be very busy. Examples, are summers, fall and spring breaks, and Christmas and Thanksgiving breaks.
The 2nd-6th will be less busy than Jan. 1st of course, but that week will be PACKED because most kids are not back in school yet. I think the least busiest days will be the 5th and 6th, with possibly the 6th being light crowds.