On NASA's giant orbital map, there are numerous lines and abbreviations.
SAA stands for South Atlantic Anomaly or the high radiation area.
I'm guessing the two large areas marked by lines stretching almost to
the poles are TDRS coverage areas, is this correct? It seems to
indicate that the TDRS gap is right over the USA, which doesn't seem
correct.

Are the other areas ground tracking station coverage?

When the ISS is shown on the map, there are considerable more areas
drawn, particularly over Russia, so I figure these show Russian ground
station coverage areas, is this correct?

HTSS appears to be a ground station in Hawai'i, and GTSS another station
in Guam. What are some of the other abbreviations on the map?