The first iMac G3/500 was the DV-SE in Summer 2000 (Graphite or Snow), with 9.0.4. The second was the Indigo/Flower Power/Blue Dalmation bunch in early 2001, with 9.1 (and, later, 10.0.3 also). The third (Indigo/Snow) was released in Summer 2001, with changeing configurations. Even if yours is Indigo, that is perhaps not as conclusive as the processor version, in conjunction with the release date, for identification: 83.0, 33.11 and 22.15 respectively, together with the video RAM complement and original optical drive. Not until you can open Apple System Profiler is that knowledge accessible to you, however. You probably know nothing of the iMac's history (repairs, mods and so on), so the only safe course is to assume that it has no firmware updates (2.4 and 4.1.9), that it can boot into nothing later than OS 9.0.4 (or 9.1), and start from the bottom. If the firmware updates are already present, the iMac will tell you .
There are some things related to the target Mac's hard drive that you can do in target disk mode, but firmware updating must be done while the iMac is booted locally in OS 9, as the instructions make clear. The firmware updates also include improvements to FireWire behaviour, including booting from external drives. As insurance, it is also wise to install OS 9 drivers during formatting of your HDD so that you can have an alternative to OS X as a startup OS when you are troubleshooting.
Jumpering necessity depends on the drive, not the iMac. Seagate drives can tolerate no jumper if the drive is solitary. Maxtor, Western Digital, IBM and Quantum have their own ways, sometimes model-dependent. Since you have two drives on the bus (of necessity), you need to consult your drive manufacturer's literature.
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There are some things related to the target Mac's hard drive that you can do in target disk mode, but firmware updating must be done while the iMac is booted locally in OS 9, as the instructions make clear. The firmware updates also include improvements to FireWire behaviour, including booting from external drives. As insurance, it is also wise to install OS 9 drivers during formatting of your HDD so that you can have an alternative to OS X as a startup OS when you are troubleshooting.
Jumpering necessity depends on the drive, not the iMac. Seagate drives can tolerate no jumper if the drive is solitary. Maxtor, Western Digital, IBM and Quantum have their own ways, sometimes model-dependent. Since you have two drives on the bus (of necessity), you need to consult your drive manufacturer's literature.
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