Are you running KatMouse? I was having this same problem recently, but I found that Chrome scrolled naturally when I turned off KatMouse.
Setting KatMouse to ignore chrome.exe didn't have any effect, but setting special handling for the Chrome_RenderWidgetHostHWND class let KatMouse play nice with Chrome. I used these instructions from http://eng.raneri.it/blog/2009/09/29/google-chrome-how-to-fix-the-fast-scroll-issue/ . First, right click on the KatMouse icon and choose Settings.
Then, switch to “Classes” tab and start Google Chrome: drag and drop the KatMouse “target” icon to the main section of Chrome windows (the one where web sites are rendered); you’ll see a new item named “Chrome_RenderWidgetHostHWND” in the KatMouse list: double click it and choose “Custom scroll”, then set it to “1” and confirm with OK.
This worked for both the page content and the element inspector.