I had issues with this on a similar (teal G3) iMac using openSuSE 10.3 and 10.2- it's nice to see you got a lot further with 10.1, even if there are a few bugs to work out.

Selecting default updates is usually ok- YaST will check dependencies for you and let you know if there's anything else you need- and usually one more click will take care of it. Selecting all packages will include all available updates, not just the recommended ones. I find that there's usually a couple of automatic ones at the bottom that I don't need, like the nVidia video driver installer when I'm using an ATI card. Most of the recommended ones are a safe bet, though.

Forcing a G3 to boot from external source? I'm not sure how- I only know a few boot options, like holding "C" when turning on to boot from internal CD-ROM. Beyond that, I'm just about useless on a Mac. That's part of why I'm trying to learn how to set up SuSE on a G3 that was offered to me for free- so I can be marginally more useful in this area.

Deleting partitions is a tricky one- I wish I knew, because I'm having the same issue with my firefly drive. I loaded it up, but somehow it has become read-only, and now I can't clear space on it.

Wow- I'm not much help here. Is your CMOS battery having issues, or your hdd starting to make odd noises? That's about the only time I've seen a desktop fail without it being relatively obvious that you've done something specifically wrong (like wrong video drivers, resolution issues, or changed/moved a critical file and the OS can't find it anymore.) It could be as simple as applets trying to run on hardware that isn't capable of handling them.

Finally, the networking issue has to do with Samba settings and open ports. Just because there is no "active" firewall on the rest of the network, that doesn't necessarily mean you have the correct ports open on your machine. There are threads in the networking forum about this specific issue, along with several attempts to solve it. Key items: enable SSH in SuSE firewall settings, share the devices on the Windows side (you probably already have this part set up), and double-check Samba settings. Linux networking seems to be more art than science sometimes, but I would recommend posting about that part in the networking forum.