A sort of sci fi comedy 70's-80's and the only scene I remember is a red blob like alien ripping a scientist to shreds and the scientist makes excuses saying "it" just wants to play.

The Creature Wasn't Nice (1983)
Aka Naked Space
Aka Spaceship
Starring Cindy Williams, Bruce Kimmel (writer/director), Leslie Nielsen, Patrick Macnee (dismembered scientist)
IMDb synopsis:
When the spaceship Vertigo stops to explore a previously unknown planet, the crew finds an unrecognized dollop of protoplasm and takes it aboard ship to return it to Earth for analysis. On board, the lifeform expands into an oozing person-eating monster which communicates primarily by means of a Vegas lounge act. The crew is gobbled up one after another until the two surviving crewmembers come up with a plan.

The Creature Wasn't Nice (1983) - IMDb (http://www.imdb.com/title/tt0082213/)

Here's a film clip:
Naked Space or The Creature Wasn't Nice or Spaceship - YouTube (http://www.youtube.com/watch?v=mbdhF-jHSYM)