The edit window is your friend. Once you have highlighted your section you want to copy blow up the edit window for each track. Reason being some instruments start before the actual bar starts. When you find one of your rt's does this, zoom in and place your cursor at the zero crossing point. Note where your cursor position is on the current box. Type this number in the "from" box. Move to the end of your section, repeat and type this number in the "to" box. Now your section will be highlighted with your best and most exact starting and ending points. Copy and paste to the desired track using your starting point. For example, if your starting point is 12 - 4 - 119 and you are pasting to bar 32, then you'll paste at 32 - 4 - 119 for that track section.

There are other ways to do it mentioned above, but this way you will get cleaner edits.