Aliens (1986) special edition, is about 15 minutes longer.
The extra footage is mainly at the beginning when some of the colonists, Newts parents, find and enter the alien ship.
It's my favorite of the Alien movies.
This is slightly OT but probably the best place to put it.
On Monday US's Memorial Day HBO2e&w (502/505 on DirecTV) are running the excellent complete Band Of Brothers miniseries starting at 0900. Set your VCRs!
"ET: The Extra Terrestrial" from 1982 One of Cinema's Greatest Films.
As enchanting and magnificent now as what it was back then.
Under the eye of Master Cinematic Genius Steven Spielberg
There are defintely times where the tears flow down the faces after all these years.