Is there a way for me to view messages in the preview pane in Mail (i.e., scroll up or down), without having Mail mark the message as "read", unless I actually open the message? If so, can anyone tell me how I can set that option??
You have the option to close the message area by double clicking the bar separating the messaging area from the list of messages. This way, messages you select will not be opened until they are double-clicked (and will open in a separate window).
Also, by right-clicking a message you have the option "Mark > As Unread."