Hi!
Highlight (click on) one of your .doc icons.
Then File > Get Info
Two thirds down the panel, you will see 'Open With'
Select your preferred app (Pages)
Click on the <Change All> button to change all of the .docs on your HD.
And Voila! and Hey Presto! - all should now be fine!
(Although I am not certain that the future default app will remain with Pages - hmm. Sorry)