HTML Overflow Not Clean

HTML Overflow Not Clean

I have this fiddle
I use some css:
#body { overflow-y:scroll; }
to make the content area scrollable, so you don't have to scroll the page.
My aim is to have a full height side bar at all times, so I figured that I
have this content element #body have a scroll and it be fine. However, it
makes the border really weird when scrolling data, how do I get past that?
Part 2: I want there to be two panels, the left fixed width and the right
taking up the remainding width of the screen? how do I do this so that I
can have #body take up 90% of the second panels' width without having to
set a fixed width with loads of left margin?
Thanks,