If your pdf has more than 1 page, split it into single pages with pdftk. Type
pdftk mypdf.pdf burst output p%1d.pdf and you will obtain p1.pdf, p2.pdf etc.
Convert these single pdf pages into jpg with Imagemagick: convert -density 300 p1.pdf p1.jpg. You will have to research to right density so you don't loose any resolution.
Create a new MS-word document and click on Insert, Image, File, p1.jpg. The your first page should show up in your Word document. You can change its size with a mouse right-click.