Thanks for your advice guys.
In the end I opted for doing changing the H1 tags using this method:
http://www.getwordpressed.com/seo/h1-hack-for-wordpress-pages/
Basically this meant that for the pages with no new H1 tag, it would default back to using the standard title as before.
For the title I used SEO title tag ( http://wordpress.org/extend/plugins/seo-title-tag/ ) so that as with the H1, unless a new title is specified, wordpress defaults back to the standard page title system.
Once again, thanks for your help.
