To be clear here, without this lawsuit there was a real question whether these emails would actually be saved for posterity at all. While they apparently are currently in a state where they could be recovered, if they were just left abandoned or outright thrown out, they would never be viewable at that point. While there may be limited short term payoff, there is the long term issue of eventual public accountability. (With emails becoming public after 7 years for instance potentially having actual consequences for former members of the Bush administration.)

It should be noted that there are genuine emails it probably is in the interests of the US as a whole to restrict from public access for awhile. I.E. where we have spies placed in North Korea and Iran, or simply pretty insulting sentiments about specific leaders of other countries. (If you knew the moment an administration left office such a view on the leader would be made public, you would be reluctant in many cases to give an honest opinion via email period.)

Actually there is a huge point even if some of the emails actually are classified. (Normally for most of them there will simply be delay until the public can see them but they actually won't be classified.)

The key is that over time classified documents do become declassified, with this often occurring 25 years after the fact, and a large portion of such records becoming declassified after 50 years. (While a favorable Presidential administration might potentially hold off declassifying for dubious reasons, sooner or later a Presidential administration with different views is going to come along and reverse that decision.) This means eventually historians and others can get access to these emails and come to their own judgments about the Bush administration. In other words this provides the threat to future Presidential administrations that they will eventually be shamed by the unfavorable judgement of future historians and others for their misconduct. (It also will provide information which can be flat out useful for general future research by historians period.)

You appear to be missing a major reason this is a key problem in the case of a potential Air Force One. Air Force One is actually going to pretty regularly fly to various airports all around the world, only a few of which are actually likely to see A380 scheduled service. When he's not flying to a location such as Paris or London it becomes quite likely this issue will come up. The President also has a variety of reason including political campaigning which can lead him to fly to all sorts of airports in the US, of which only a quite small number will be seeing A380 service anytime soon. Even as simply a maintenance issue it would be a major liability, and an engine going out at the wrong time could be somewhat of a security issue. (Among other things you don't want to take off with only three functioning engines and there are potentially times in which it can be important for the President to be able ti get in the air quickly.) The airport accessibility concern in this case is about way more than just an exceptional diversion.

The problem is not the individual pound per square inch exerted per wheel which the A380 does effectively deal with, but the TOTAL weight and the strain it potentially puts on the tunnel structure. A tunnel can potentially take the pounds per square inch just fine, but collapse due to the substantially greater total weight placed by the A380. If you read the article I linked to, LAX didn't upgrade underground structures specifically to accommodate the A380 for the heck of it, they did so because they calculated it was necessary to do so due to the greater weight of the plane involved. (The 777-300ER has been flying into Los Angeles International Airport for awhile.)

This is incorrect.

I don't know if the taxing on inner engines is really viable, but there are other problems at some airports. (The odd thing is enlarging taxiways appears to have been treated as mandatory for all airports getting the A380, and you think some would just resort to the alternative you suggested if it was really safe and perfectly viable without problems.)

However there are additional issues at some US airports for instance...

http://findarticles.com/p/articles/mi_qn4188/is_20050215/ai_n11501106/pg_2?tag=artBody;col1/

Basically reinforcing the tunnels to handle the A380s weight is something which certainly won't get done unless an airport is seeing regular A380 service. Similar situations exist at a variety of airports in which runways go over roads. However not being able to use various airports is a serious limitation for Air Force One which will regularly get used wherever the US President wants to fly somewhere. It also is a potential issue in that it limits the number of locations the aircraft can ultimately choose to land in an emergency situation.