Although this can't be done directly from Word, it can be done in code from Excel (see:
http://dmcritchie.mvps.org/excel/xl2gif.htm). Accordingly, if you automate an Excel session and copy your tables to Excel, you can save them as GIFs, etc, from there.
In Word, you can use the CopyAsPicture method combined with PasteSpecial or PasteAndFormat to create an image of the table in the document, but those methods tend to lose border details and the add a lot of white space around the copied table.