BR...
if you remember I had PMed you the answer before...
and also mentioned it to you when I did the "Big Space of Horrors Tournament"...
but here it is...for you...once more...:)
Galaxy of Terror (1981)
http://www.imdb.com/title/tt0082431/
It isnt out on DVD yet. Try this link at amazon, maybe you will find someone you ll sell it to you :-
http://www.amazon.com/Galaxy-Terror-...e=UTF8&s=video
Cheerio...and smile because "happy, happy days are here again..."
:D