Not true. A standard DVD contains a maximum of 720 lines of resolution. "Upconverting" to 1080i or 1080p does not add information that wasn't there to begin with; it either extrapolates the extra pixels or it doubles existing pixels. You may or may not notice the difference, but the difference is real nonetheless. Upconversion is not magic.
I agree, but like you said, will you notice? Probably not unless you are less then 5 feet from the monitor and have a monitor larger then 42”.