Hello i am new to the forums and this looks like a very informational forum. So yeah...
Q1-I know that you can change the icons in the shell32.dll file. But i would like to add icons to it. Is it possible?  
 
Q2-Also, how do i change the defult folder icon with res hacker?  
 
=Thanks for your help= sorry if this is the wrong section to post this, im not sure cause im a nebwie

A1 Yes you can change the icons in Shell32.dll You can use ResEdit or resource hacker for that (But it's a risky approach to follow - never try this unless you're 100% through with it )
 
A2 After you've selected the icon from the tree (The Drop down menu in left) Go to Action>Replace Icon In the appearing window select a file with new icons (like a .dll .exe etc) and choose the icon & hit 'Replace'