One way you could do this would be to delete all the page types that you have installed or active, so that only the one you want to use is available.

OR.. you could use this super-handy FREE addon to add many pages all at once, which would all use the same page type (that you specify).

http://www.concrete5.org/marketplace/addons/add-multiple-pages/...

I hope this helps.

In the Dashboard go to Sitemap, Page Search.

In here you can filter to list pages by a particular page type, if necessary. Check all the pages you want to change the page type of (or hit the checkbox at the top to select them all).

Then use the '** With Selected' drop down above the list and pick 'Design'. Pick the page type you want them to be changed to and hit Update. This will update all the pages to the new page type in one go.

Note that on this page there is a Per Page drop down, if you've got lots of pages on your site you might want to adjust this settings when searching so you can display all the pages in one list.

The pagesearch worked good. one problem i always have is when a page type is changed i loose some of my content due to different blocks per theme or pagetype. any solution for this?

I am afraid that is going to happen no matter what as far as I know.

One thing you could try is to copy the blocks to the clipboard and then change the theme. Then paste those blocks back where you need them in the new theme. I am not 100% sure this will work, but it is worth a try.

Also, based on my own experience, if you change a theme, it still keeps everything, the new theme just might not display everything. Then if I change the theme back, it will restore everything like it was before you changed the theme.

I hope this helps.