How to change the look or appearance of scrollbars in windows XP

I am trying to change the color or contrast in scrollbars cause I can-t see the current position (difficult to find). I have read that themes overwrite the value in regedit.

What I did is this...

Win+R,
regedit,
HKEY USERS,
s 1 5 19,
Control Panel
Colors
Right there I changed the numbers of 'scrollbar' (¿RGB?) 186 105 20

Well, Windows XP visual themes use graphics rather than shapes and colours so you'll have to gain access to the resource file, edit the scrollbar graphic and then recompile. I won't go into the specifics but if you download a free program called "ResEdit" by searching it on google and then open the resource file which is c:\windows\resources\themes\lunaX.msstyles. Just save your edited style out under a different name then click on its icon. This will call up the properties page so that you can save the theme out.

Ok, THANK YOU.