There are some filters for VirtualDub IIRC. Try Googling old cinema filters and/or VirtualDub old cinema filters. Windows movie maker also has some basic old-film filters.
I believe there is a movie makers forum for original Il-2 where these questions can be better answered. I spend quite some time in FMB but have no idea on how to follow a plane with a mouse to make it look smooth
Maybe some (Alt-CTRL-Shift) F4-F9 external views?