I'm having trouble finding information on describing the changes between Olde and Modern English, such as OLD ENGLISH hlaf and loaf; what is best way?
I would appreciate comments on the best way to describe the changes that occur between OLD ENGLISH hiaf and loaf, GERMAN breenen and ENGLISH burn, OLD ENGLISH thurgh and MODERN ENGLISH through, EARLY LATIN inpossibilis and LATE LATIN impossibilis and OLD ENGLISH heofod and MODERN ENGLISH head.
This is the branch of linguistics called “diachronics” dealing with etymology—how and why word formations change over time. My suggestion is that you develop a bibliography (book list) of reference material available in a good college library (where you can physically browse through the rows of books on this subject), gradually narrowing in on studies of Old English/modern English morphologies (use the bibliographies at the end of each study to further your search.) Each of your examples has a separate “explanation”; rest assured that scholars have examined every one of these “morphs” for a hundred years. You might want to start with an introductory textbook on Morphology itself, to familiarize yourself with the terminology of the discipline. At the base of your inquiry will be changes that occurred with and because of the invention of the printing press (until that time, language was predominantly an oral transmission.) Many morphological changes occurred simply because words’ spellings were being regularized. Good luck on this long and intricate inquiry. A brief addendum: some of your examples are part of "the great vowel shift"--you might want to start there.