There are some small differences in the gameplay as well between this two versions. These are the two considerable changes in the gameplay in the 10th Anniversary Edition compared to the Settlers 2 Gold.
Regarding the military you are able to upgrade military buildings into bigger ones (if there is enough space for a bigger building) and military buildings can exist without any soldiers in it in the 10th Anniversary Edition. After soldiers occupied a military building you can recall them back without losing the land you have conquered and the building will remain empty until you send forces back into.
Regarding the economy there is a small change if you demolish buildings and the building times. In the 10th Anniversary Edition you get half of the resources back if you demolish a building, so you can't get to a dead end anymore where you ran out of wood but can't build any woodcutter or sawmill due to the lack of wood. The building times have been reduced up to 50 % so the gameplay is a bit faster with less waiting time and you can accelarete the game up to 3 times as fast instead of just double the speed.
Regarding the campaigns, the 10th Annieversary Edition doesn't include the Campaign of the expansion of the Settlers 2 which was a world map on which you had to conquer every continent. And as far as I remember the campaign in the 10th Anniversary Edition is not a copy of the original campaign but has 10 missions as well.
Here are two links, translated with google since they are german: https://translate.google.de/translate?hl=de&sl=de&tl=en&u=http%3A%2F%2Fjh-isch.de%2Fs2%2Fseiten%2Fdng_unterschiede.php https://translate.google.de/translate?hl=de&sl=de&tl=en&u=http%3A%2F%2Fdiesiedler2.de.ubi.com%2Fgame_changes.php