We are potentially looking to go in March, there are just 2 of us, DH and me. Is there a good site to check for crowd calendars?
There really aren't any super reliable crowd calendars for DLR (there is no easyWDW-equivalent for example). Some folks using Touring Plans, others recommend IsItPacked.com. Take all of them with a large grain of salt. When are you thinking of going in March? Easter is on March 27 in 2016, so expect high crowds the week before and week after Easter (the peak of the Spring Break-season). We don't really know what else will be happening in March at this point, but you can check out the
2015 Calendar of Events thread to get a sense of what events (e.g., conventions, cheer camps, etc.) happened in March of 2015 as a point of reference.
We are looking at staying at a Good Neighbor Hotel. Are there benefits to book it through the Disney site v. the hotel's site? Also, can you use a
travel agent for DL good neighbor hotels?
I don't know the details about a travel agent. Mostly, unless you're coming from a really far distance, DLR is generally small enough that I think most people can book their own trips. In terms of the Good Neighbor Hotels, unless the price through Disney is better, I would book directly through the hotel. If you have to cancel a Good Neighbor reservation it's basically a two step process (you cancel through Disney, then they cancel with the hotel/motel). I did this once and ended up having to deal getting no show fees refunded because I cancelled with Disney, but they didn't follow through a cancel with the hotel, so the hotel considered me a no show. It wasn't hard, but it was time consuming.
I was looking and couldn't find any information about the photopass, is that an option?
Yes, DLR still uses the Photopass Plus system. You can either pre-order it ($69.95) or you can purchase it at the parks ($99.95). It includes the photopass photographer photos, the attraction photos, and the character meal photo packages.
http://disneyphotopass.com/specialoffers/dlrppp.htm
How far out do we need to make any dining reservations? Is it like WDW where you need to do some right on the 180 mark?
No, as the PP said, dining reservations do not open until 60-days in advance at DLR. The operating calendar is released approximately 45-days/6-weeks in advance and the entertainment and MM/EMH schedule is often no complete until closer to the 30-day mark. Unlike WDW, you do not need to be online right when the system rolls to get the prime dining ADRs. In fact, we don't really know for absolute certain when the system rolls (sometime after midnight, but before 6:00 am). You can often wait until much closer to the date to get great times and locations. That being said, if you know you want to eat somewhere and/or at a specific time, I would still go ahead and make an ADR.