We transferred an old website with hundreds of pages and many languages to Joomla 2.5.6. All content on old website has .htm suffix. In view of search engines rank, what is better to use: redirection 200 (opening old .htm address with new .html content) or 201 (redirecting old .htm address to new .html address)?

Thanks Luigi, you're probably right, but could you give me the example of using regular expressions and macros? Don't I have to redirect each individual old URL to its corresponding new URL?

We've decided to go for 301 redirections but we encountered a problem. Old website used Joomla extension for SEF links and it has some links written as folders but there're also additonal links connected to that folder. We want to define specific redirects but if we make a redirect for old folder, all links that contain that folder in their url address also get redirected to the replacement for folder. For example:

/foldername/ gets redirected to /newfolder/newfilename.html

We want file /foldername/filename.htm to be redirected to new link /newfolder/somefilename.html

but it gets redirected to the above link (/newfolder/newfilename.html)

How can we avoid this and have each file being redirected to its own replacement regardless of the same folder? I placed second redirection before folder redirection but it does not have any impact.