Most of this is outside
my little world of knowledge, but I'll do what I can with hopes that others might be able to help. In order:
DCT: Discrete Cosine Transform is a compression technology.
525i and standard definition 480 horizontal lines @ 60 frames per second are the same.
This is an "overscan" number of horizontal rows.
For standard definition, yes, this is current. Many have moved to high definition 720 or 1080 horizontal lines of video resolution.
There is no "lossless" video capture/storage. All compress - some less or more than others.
SD = Standard Definition video. As DV format captured to miniDV tape, yes, it is compressed (less than other formats).
I have not used Pinnacle - sorry.
You might be able to get better video quality (the Pinnacle users get to chime in here), but the files will be even larger (taking longer to load for playback).
And thank you for the outside shots. They reminded me of my teen years and boating/water skiing near the Naval Air Station...
Ha'oule Makahiki Hou!