I would suggest you look at this thread and this thread.
C/C++ are THE BEST for speed. For object oriented designs and running on multiple platforms it's Java, and for running on only microsoft with fast development times (but tons o errors as we all know) it's VB.
Note. C/C++ are not relegated to *nix. Remember that DLL's are written in C/C++ too.
My personaly favorite is Java but that's just cuz I learned it in uni and have taken many high level courses using it.
