When I select ‘Opendocument text’ to create a new file on the desktop, it defaults to an .odt doc, not to a .doc or docx.
Is this ‘feature’ or a problem. If a problem, where do I go to find a solution?
This is not a problem, that is perfectly normal. For LibreOffice, the native document format if OpenDocument, which has file extensions like ODT/ODS/etc. LibreOffice can open and save documents in lots of other formats, like OOXML (native to MS Office; extensions like docx/xlsx/…), but those other formats are “foreign” to LibreOffice, and are not supported to the same extent as own native format. Thus, when LibreOffice installs, it creates shell shortcuts (here I mean the quick way to create new documents using New menu in Explorer) for own native formats only. Creating such shortcuts for DOCX and the like would be misleading, creating an impression that LibreOffice support for those formats is “perfect”, encouraging using those formats as primary when working with LibreOffice, and finally leading to problems when something gets lost from documents because of imperfect support. Have you seen a warning when trying to save from LibreOffice into DOCX, telling you that something could get lost? That warning is there for a reason.