I am new to 1942 2nd edition too although I did play 1-2 games of the classic version (MB). Picking this game up again brings me lot of good memory ;-)
Something I notice that has changed (you probably can find a more detailed description from some other page in this forum)
Map - Map is key difference and it makes some classic strategy more difficult to pull off.
Default set up - This changes a lot. Russia used to have a lot more resource to start with and in this version it’s less. England now has a factory in India by default.
Rule - Some rules are changed - for example you cannot put unlimited amount of recent purchased units in the same territory; transport cannot be used as casualty unless it is the last resort…etc
Price - Like Armor - it now costs 6 instead of 5
No more research weapon thing
Different option rules (like Russia cannot attack on 1st turn rule)
Different winning condition (now it has victory cities)
It’s a fun game! Give it a try - I am still learning how to beat the Axis efficiently in this new version!