Good ideas from Patrick. Think about using iPhoto. The iPhoto interface is pretty friendly, and the capabilities are between iDVD and iMovie. Since most of my slideshows are straightforward, I like to use iPhoto because it is easy to organize my pictures (import into iPhoto; drag them to a new Album, and move them into the desired order). After you click the slideshow button, you can set a default duration (I use 5 seconds), and transition (tough to beat a gentle crossfade), and then adjust individual slides if desired (longer for group photo; perhaps shorter for a picture of Fido). You can't get fancy with music crossfades or precise photo/music timing, but I don't need that very often (add music by setting up a playlist in iTunes and add to your slideshow in iPhoto). I'll create my titles in Photoshop Elements and import jpgs into iPhoto just like a photo (PSE gives me lots of control over your title slides).
To go to iDVD, use Share/Export in iPhoto and send to full quality Quicktime. You can check the resulting Quicktime movie to make sure it works like you want, then drag it onto the iDVD menu area (not a drop zone). Use a nice photo for the iDVD menu background and you'll have a very nice-looking final product.
If you do a search for slideshows here and in iMovie, you'll get more suggestions as well.
John