A polite request:
When asking for software recommendations, please tell us which operating system you're using.
Any DTP package can be used to easily design DVD covers. Serif PagePlus SE is well-reviewed (and free!):
http://www.serif.com/...tware/?mc=FSSPAGEPLUS
(It runs under XP, Vista and 7)
For a dedicated program, UnderCoverXP is popular. It runs under Vista, as well as XP and earlier versions of Windows, but doesn't support Windows 7:
http://download.cnet....-6675_4-10790541.html
This might also be worth a look (particularly if you've got Windows 7):
http://download.cnet....-2191_4-75307738.html
Chris