The best way to learn a new language is to use a barebones IDE such as BlueJ (for Java) and Dev C++ (for C++)... Using these will ensure that you do all the coding yourself instead of relying on a software to insert code snippets etc...
If you want to use it for programming once, you may not be particular about picking up nuances of the coding... In that case, you can go for powerful IDEs like Eclipse/Netbeans...
BTW, the best help for Java is found in the Sun Java website (a few downloadable tutorials, and the documentation for the classes)
I have heard a lot about Eclipse, though never used it.
I used Sun Java Enterprise Edition 8 for my final year project and it did my work just well.
And yes, it is resource hungry.
Since you are new, I highly recommend BlueJ.
It is a very user friendly IDE, later you can try using Eclipse, which is also very good.
BlueJ can be got at: www.bluej.org