change the theme to window classics, and change the appearance to windows classics
click start, run, type msconfig, in startup uncheck all of the item you don't need to run in start
right click toolbar, select properties , start menu, customize, set the the number of programs on start menu to 0, click advance, uncheck "list my most recently open documents" and select clear list.
get rid of norton antivirus, it is a resource hog. use avg or avast
this should give you anywhere from 75 to 150mb of extra ram