I have a few websites with graphics that need minor modifications, and I can't for the life of me figure how to edit layers of .psd files using gimp / windows

I can find all kinds of tutorials that get into all kinds of fancy effects, all I need to do is change some of the text or cut a portion of the text.

For example one site has a header "Christmas 2011" I'd like to change it to "Christmas 2012" or even "Christmas" would be suitable.

In the case of the psd for that image, the "Christmas 2011" seems to be in it's own layer.

Here's a link to the png & PSD files if anyone cares to look at it http://id72.com/imagetest.php