I have two questions about software for managing digital camera
photos, using Windows 98.

(1) I would like to be able to display the photos in a folder as a
full-screen slideshow, and delete them (and possibly rotate them)
along the way.  Is there software (preferably free, or at least
downloadable, that does this)?

(2) I've noticed that more recent versions of Windows have things set
up so that picture folders (under "My Pictures") automatically display
thumbnail images for picture files, and enable slideshow viewing as an
option displayed in the folder.  How can one get a similar set-up
running in Windows 98?

Try the freeware "Irfanview". Does much more than slideshows and is very stable.

I use ThumbsPlus 3.1 by cerious software.  The 3.1 version is older,
but I have found it very non-taxing on my system when it is used.  I
do not have much experience with other programs that have the
slideshow function.

Once installed, you can create a folder and throw all of your graphic
images (slides) in that folder and then click a button and the slide
show begins.  Very easy to use, and the other graphic tools are very
helpful.

ACDSee does the job also.

Turns out Irfanview worked well, for the first part of my question.
The second part is less important, anyway.  Thanks!