The original TNG episodes still exist, but they cannot be "uprezzed" to HD...
I don't know... the episodes look pretty decent up-scaled to 1080p on my 40" LCD.
They look terrible to me up-scaled (and the up-scaling done for "Trials and Tribble-ations" on Blu-Ray looks equally bad). They look even worse when they're cropped to 16:9. But YMMV.
I do have to draw exception to an earlier comment that turning TNG into widescreen would make it more "cinematic," though. I shudder at the thought of cropping Citizen Kane
from the original 1.33:1 aspect ratio to 16:9 in order to make it more "cinematic." 1.33:1 was the standard aspect ratio for movies for several decades.