I hesitate to discuss this because it's a little too close to my work. First, imagery satellites aren't orbited anywhere near that low because their orbits would degrade too quickly. Being deliberately vague, they're a few times higher than the orbit you described. That would translate into a slightly longer viewing time for any particular point on the Earth but also impacts your resolution numbers.

More to the point, there are two basic types of imaging sensors used on imagery satellites. One type, as used on the Hubble and Clementine, uses a 2d matrix CCD that takes images like a digital camera. A more common technique is to use an essentially 1d CCD (say 4096 x 1 pixels) like the one used on MGS. These imagers are sometimes called "push broom" cameras. They look at the surface below and record a stream of data as the satellite flies by, as shown here. It's an electronic equivalent to the strip film cameras used on early satellites like the CORONA program*. If you're using a strip camera, you can't take moving video images like the ones shown in the movie. If you're using a 2d CCD, you can take video as long as you have the bandwidth to transmit the data.

Now, admittedly "Patriot Games" got a lot wrong. Still, it was a lot more accurate than some other movies such as "Enemy of the State". Like "Armageddon", it's easier to point out the things they got right than the things they got wrong in those movies. The short answer is, "Not much."

*The strip camera was first used to capture the "photo finish" at horse races. George Goddard, a pioneer in American aerial reconnaissance, adapted the camera to take pictures from high speed aircraft flying close to the ground in WWII. Some of the best pictures of the Normandy defenses were taken by strip cameras on highly dangerous "dicing missions" shortly before D-Day and the Navy made extensive use of the camera for invasion planning.