Parts of Germany were ruled by Rome, but be aware that much of the country was either never administered by Rome, or for some parts only briefly during Augustus's attempt to advance the frontier to the Elbe.

England was conquered by the Angles, Saxons, and Jutes after it had been effectively abandoned by Rome; unlike other Germanic tribes which took over pieces of Roman territory, they did not undergo the linguistic shift to pick up that Latin of the conquered region. Why this is would be an interesting question for someone to explore more deeply, but Britain was perhaps more at the fringe of Roman control, and not in the Roman "heartland," where figures like Theoderic, king of the Ostrogoths, had ambitions of replicating/replacing Roman grandeur and achieving some sort of parity with the Eastern emperors, using his adoption of some (but by no means all!) elements of Roman culture to show off the sophistication of his new state.

The eastern portion of the Empire (like Greece) did not Latinize as much as the west even during the rule of a united empire; Greek was already an effective unifying language throughout the region since the Hellenistic Age, and to grossly oversimplify things, you tend to see much more in the way of Rome accommodating Greek there (educated Romans for much of the time period that Rome ruled Greece tended to learn Greek), and in any case tremendous portions of the eastern part of the empire and northern Africa underwent another very significant cultural/linguistic shift after they were appropriated by the Caliphate, which brought the Arabic language, or by Turks, who brought their own.

You might want to consider the opposite question of why the Romance languages prevailed where they did, as opposed to various alternatives. Both questions are the same -- there is no single answer, but rather it is wrapped up in the unique history of each region/country.

There are also many places in Europe where Latin either died off or never took hold, and a (post-Latin) Romance language came in later. It's unknown/debated if Romanian evolved from a continuous presence of vulgar Latin in the area, or if Latin died off completely with proto-Romanian introduced afterwards by migrants (and dying out where they came from); either way, the Romans never controlled the entire area where Romanian is the predominant language today.

First off, some of the regions you list actually did speak Latin at one time. England had a good amount of Latin speakers before it was abandoned by the Romans and then colonized by the Anglo-Saxons, and western North Africa was almost completely Latin until it was finally captured by the Arab Caliphate in 698, after which Latin was slowly replaced with Arabic.

The main reason why the east never latinized was because, by the time of the Empire, Rome was essentially bi-lingual. Around half the population of the empire lived in the east, where almost all the important people spoke Greek, so Rome adapted by administering that half using Greek and native Greek speakers instead of trying to force Latin upon it. This acceptance and integration of the Greek language was a major reason for the development of a strong Roman identity in the east in later years. Emperor Claudius once commented to an ambassador who spoke Greek and Latin that he was "impressed you know both of our languages".