New install with old content

I am trying to upgrade a site with a very old version of WordPress, and thought I would try setting up a mirror site so I can test the new design (tried to set up a local server but I just can’t get it to work…this seemed like an easier solution). I installed WordPress into a new folder, but now want to take the content folder of the other site that I’m upgrading and just replace the standard wp-content folder that came with this new install to get the other site appearing on my mirror site?

I already tried this…I installed all the new WP files with the old content folder and could not get anything to show up. I was logged in, dashboard showed up fine, made a test post…but when I tried to view it, it was just a blank page. So I deleted the old content folder, replaced it with the standard one from the new download and now I do have the basic new-install “welcome” homepage appearing. I imagine if I just try to replace the content folder again, it will just go back to the blank page I had before.

So what steps am I missing? How can I import the content from the original site that’s running on 2.2.2 to this other folder with 3.0.1 running? It’s A LOT, the site is 3-4 years old with lots of images, so everything in that folder needs to get over to this new site somehow.