The file extensions on your computer has been set to open .pdf files in "word" format for some reason...and this will cause all PDF files to be opened in Word format.
You can change this in the following steps:
1) Close all programs etc...come to desktop with icons
2) Click on Start > Select Control Panel> Select Folder Options
3) Select "File Types" on top> Scroll down until you find items such as PDF, PDFXML, PDX
4) Select each item and click "Change"> From the list select "Adobe Reader" for each of these items> Click "Ok"> Click "Apply"
5) Finally click "Ok" to close that "Folder Options" screen> Close Control Panel
Note: Do the "Ok" and "Apply" step for each of these items each time to make the changes.
Now you should be able to open .pdf files in PDF format