Click Tools > Options > Actions  (or click the Action toolbar button) or Alt + T 
Click the New icon
Enter a name for the action - eg: Rename folder
Action window pops up
Click the New icon
Select Action type - format value & Click OK
Select Field _DIRECTORY
%artist% - %album% (%year%) [%_extension%]  << problem here [] don't appear. must be a reg ex thing.
Click OK, OK
Click the Actions button , ensure the tick mark is ON for rename folder and click OK to rename the folder..
The folder should be renamed using the info already stored in the tags.

eg: Lil_Mo-Pain_And_Paper-R&B[www.dodgeysite.com]

becomes 

Lil' Mo - Pain & Paper (2007) [mp3]