Connecting to Samsung HDTV

I have recently purchased an HDTV and want to connect it to either my iMac or macbook.. my husband went to the store and after speaking to 4 people got a mini dvi-vga converter, a vga cable and an audio cable and they said that would work.
What happens is only my background shows up on the tv screen when I try it on either computer (no other windows i have open show) Am I missing a step?

go to sys pref / display / arrangement and click the mirror displays and then every thing on your Mac will be on the tv.

and for all your questions on this set up here is a great guide:
http://www.mac-forums.com/forums/other-hardware-peripherals/193239-connecting-your-mac-your-tv.html

hope this helps
Clay

thanks!

That worked perfectly, thanks so much!

glad to help
Clay