I am a digital packrat and I collect a lot of the same type of files you do...tons of clipart, stock photos, vectors, icons, etc.
Extensis Portfolio is worth every penny of its $199.95 price tag (single user edition). This is software made for the pros and there are multi-user and server versions of it that are quite expensive that big companies use. It's powerful, but not bloated like Adobe products.
If you catalog everything as you acquire it, it's so much easier to deal with. And you said you wanted to burn it to DVD. Extensis makes that easy by collecting, organizing, and packaging the photos and including a copy of the database, linked to the full size images that will be on each disk.
You can include so much info for each image and assign as many keywords as you wish. And it's pretty speedy once the images have been cataloged. It creates the thumbnails or extracts them from the original (if they exist) and they become part of the database. It doesn't have to go find the original file and create a new thumbnail each time you browse or search. Browsing through 1000's of files in Portfolio is faster than waiting for Explorer to render thumbnails for a large folder full of images.
And it will make thumbnails for a lot of image, document, and audio/video formats, including AI, EPS, and a lot of RAW formats. But you aren't limited to that. You can literally catalog anything with it.
I am currently using it to collect, catalog, and organize a ton of free, public domain, and CC licensed stock photos for a friend's project, assigning keywords as I go along. When I am finished, I'll export the whole thing for burning to disk, and it will include a freeware redistributable application for viewing and searching the database. (this is provided with the software)
Screenshot:
How to manage large clipart collections?I have the photos organized in folders according to what site they came from. In each folder I have placed a text file with the license info for use of the images. The software watches the folders for new images, and will add them to the database when I manually sync the folders (I have it set up this way to make assigning keywords easier, so I don't miss any)
If you have been as much of a maniac about renaming files and organizing them with descriptive folder names, as you said, the software can automatically assign keywords based on file and folder names to make the job much easier on you. And it's pretty customizable, too, with an assortment of different view styles and will order the view based on a ton of different information.