Not in a I'm-so-tough, kinda way- but I can't recall any of them frightening me as a kid. Alien unsettled me, I believe...
I don't completely remember. I do remember, I just found Alien fascinating, more than any other film or entry in the series.
I remember asking my Dad, if it was going to be "-one of those stupid looking bobblehead aliens."
And he just replied; "No."
I wish I could remember more.