Photo archiving software...which one?

[christmasdisplays.co.nz]

Hi guys and gals. Can anyone suggest a good program that does the following;
I have thousands of photos I want to put onto dvd, however I want to be able to find individual photos easily.

I want to load them into a program, then back them up to dvd. When I search for say 'trees' then it will show me a thumb nail of the photo and which labeled disc it is on, rather than keeping my photos on my hard drive. Obvious free or cheap is what I'm after, but any suggestions are open.

Thanks in advance.
Duane