R Commander: A Basic-Statistics Graphical User Interface (GUI for R).. It has a menu driven interface to many R commands and facilities. There are numerous plug-in packages on CRAN that extend the menus to many additional functions and packages (All plug-ins havenames of the form RcmdrPlugin.* (e.g., RcmdrPlugin.survival). There is also a help system specific to Rcmdr.
After installing the package( install.packages("Rcmdr", dependencies=TRUE)), load the package with a library(Rcmdr) it then starts automatically in a separate window with the menus. If you exit the commander during an R-session, type Commander to start it again.
Here's a commented view of the R-commander window.