Depends upon three thing;
How complicated you want it to be?
What operating system you're using?
How much you want to pay?
If the answers to these questions are; "not very", "windows" and "nothing" then I'd suggest Dev-Cpp (which I use)
This is an IDE - an Integrated Development Environment - which looks very much like a basic word-processor (it is!) but has all the necessary add-ons to let you compile and run C++ code.
It also comes with all the necessary C++ libraries -- a critical requirement if you want to get up and coding without delay.
The Dev-Cpp web site is here (sorry, but I'm not sure we can load clickable links on this forum);
http://www.bloodshed.net/devcpp.html
And there's a link on this page to download and install.
You can also subscribe to their forum;
http://sourceforge.net/forum/forum.php?forum_id=128327
BUT ******WARNING****** the guys on the Dev-Cpp forum are NOT very tolerant of people asking questions to which answers are already found in the FAQ. They ARE, however, very knowledgeable and give very good support--which makes Dev-Cpp a pretty good choice.
Unfortunately Dev-Cpp has no Linux or Mac compatible version -- so for these systems you'll have to go elsewhere.
Finally, for a list of C/C++ resources (including compilers, IDEs and etc) go here;
http://www.thefreecountry.com/compilers/cpp.shtml
Best of luck