The problem with Lem is that most of his stories are not entertaining at all, if you are not able to find any greater substance within they will be just boring.
But you all are lucky because I read pretty much everything from Lem and can tell you which stories to avoid
Or better which stories to read:
Shortstories (directly translated from german, don't know the english titles):
Dr. Diagoras
The Truth ("Die Wahrheit")
Books:
Hospital of the Transfiguration (not SF)
Highcastle: A Remembrance (some kind of biographie but pretty interesting)
A Perfect Vacuum was ok but some "stories" were horrible in the respect stated above.
As mentioned:
The Investigation (it's about... ZOMBIES come on and read it NOW)
The Invincible
The Chain of Chance
If you like what you read you could try Return from the Stars.
I had to read 1984 in school which is always somehow offturning but in the end I liked some of the concepts. The idea of New Speak is amazing.
I don't think of Lovecraft as horror. It's just not frightening. I could read a lot of it because I can partly enjoy this old-fashioned style of writing and to a big part because the more stories you read the funnier they become.
They are all pretty predictable and some of the paragraphs are just pathetic (like the often repeated line about the forbidden books the main character read).
Bram Stokers Dracula is a lot like Lovecraft. I just couldn't take it serious.
Yes, Hitchhiker's Guide to the Galaxy is awesome but I guess ou all read it already, right?