Best compiler. That depends on what your trying to achieve. I use MingW (GCC 3.4.5) on Windows and Linux. I use it for cross-platform work.

My IDE is Eclipse 3.4M7 (Ganymede) with CDT (C++ Plugin). This is good because it has a nice Subversion plugin that integrates well. I find CDT has good syntax highlighting, lots of customization and really good code-completion/templates. The new Release Candidate with Ganymede is a big improvement of the current stable Europa.

Dev-C++ is nice, but it hasn't received any major updates in many years. I'm not even sure bug fixes are being done to it anymore?. I stopped using this a while ago as it couldn't do everything I wanted.

VC++ is good, but it's a Microsoft product so you have to deal with all the Microsoft crap they add into it (MFC etc).