Is there any good application for image slideshows that has many transition effects?
Have you tried
Shotwell (it is default in Ubuntu)?
And there is
F-spot Photo Manager Click to install
F-Spot is a full-featured personal photo management application for the GNOME desktop. It simplifies digital photography by providing intuitive tools to help you share, touch-up, find and organize your images. It allows for importing of your existing photo collections, tagging photos with identifiers, as well as doing simple edits of photos (e.g. rotating).
And There is
Picasa : Picasa
Very well known and great image Application.
Picasa slide show:
For Ubuntu (or Linux, in general) there are:
And others. You can get ALL of them if you install a Linux distribution called "ARTISTX" (Version 1.5 liveDVD download from developer site).
There are a good number of transitions and they are VISUAL so no need deep knowledge of Linux or the use of command line. Pay special attention to OpenShot Video Editor and Imagination.This last one is FRAGILE but I am sure you will manage it.