Most people use a Graphics editor like Photoshop or GIMP (which is *Free*) http://www.gimp.org/
You could use Thumbgen i suppose, but it might be a bit fiddly.
Here’s the Template *.XCF file (which is a GIMP Project File)
http://www.mediafire.com/download/xx0ilidc056ll1p/Template.xcf
you will also need to install this font … (copy and paste it into your Windows / Font folder)
http://www.mediafire.com/download/3e51ho22n3j3vxk/MC360.ttf
when you have GIMP installed, just double click on it and you will see this …
and from there you edit the layers and text to suit your needs. (apologies for not providing more details, but a complete user guide would take a while… best way to learn is, install GIMP have a play around, get familiar it and then ask some questions)
Here’s a “Ghost Movies” folder genre i quickly did for you …
