Is there a list of things that it gives you to do? I'm not a photo guy, but when I put in a music CD or a DVD, I get a dialogue box that gives me a list of things that can possibly run the media, and there's a checkbox at the bottom that asks, "Always perform this action." (Fedora 14, GNOME desktop environment)
If F-Spot is simply opening automatically and skipping everything else, then I see how that can be annoying. You should try to finish installing your preferred software and see if multiple programs that deal with photos work. Or you can try right-clicking on what you want to open, and pick the "Open With..." option (if it's there; it's been years since I've used SUSE, and I don't recall, but I don't see why it wouldn't be in a GNOME environment).
As for uninstalling F-Spot, I had a similar problem when I wanted to uninstall Firefox. There is a proper way to uninstall things, and some programs even come with those directions. I don't think, though, that programs that ship with the system come with such documentation, but I'm sure it can be found with a little searching. Of course, I didn't bother with all of that because I can be lazy at times.
I DO NOT RECOMMEND THIS, but what I did to get rid of Firefox was first go to my home folder and input the following command:
I was relatively new to Linux back then, and I didn't know that some folders had hidden files. Anyway, listed there was a hidden directory called ./mozilla. I deleted that, and then I deleted every other file and directory that had seemed to be even remotely related to Mozilla or Firefox on my system. That, for me, worked (Ubuntu 9.04) and it stopped it from coming back when I thought it was gone.
Again, I don't recommend doing that, as I am sure there is a more sane way of going about it.