Try watching it in Black + White for even scarier; creepier atmosphere!
I was reading about something called SHADOW THEATER online, which reviews contemporary movies screened in black and white, but originally shot in color to maximize an emotional effect. Among the movies reviewed were the original ALIEN and the first JAWS movies, which look wonderful in color; but also look pretty damn good in b&w.
So one night I decided to experiment and try this on SHOCK WAVES (1977), one of my favorite tacky, horror flicks from the 1970's.
The result was fascinating! Blue Underground's DVD is grainy and incredibly "rugged" looking to say the least. This condition of the print added to the charm. The movie LOOKED like it was shot in black and white! The grain was gorgeous! The contrast between blacks and greys even more explicit. The end result was a movie that appears more frightening without color and more oppressive in b&w. I can't say this will be for everyone's taste, but if you love SHOCK WAVES and want to appreciate a viewing of the movie you will not soon forget give it a try.
I also tried the new Scorpion version of HUMONGOUS (1982) which looked pretty good in black and white and John Carpenter's THE FOG which was the best looking color movie I have ever seen in black and white!