Update: Making a Correction to an earlier post: For choice #2 the only DN SD receiver to have a analog only OTA tuner is the model 5000 all other SD units have OTA passthru only.
The 5000 allowed OTA channel to be mapped to the EPG in the same way as the 921 does. However it did not have actual guide data except for ABC, CBS and NBC during primetime hours only. The network id was setup manually when you entered the call letters. The 921 also has this feature (for analog stations) but doesn't receive primetime guide data.
Although the 5000 has analog only tuner it did have HD capability using an optional ($250) HD RF modulator which allowed satellite HD channels to be converted to 8VSB that could be displayed to a HDTV containing a digital tuner or thru a STB with digital OTA tuner. I believe it also allowed digital OTA passthru to occur as 8VSB on channel 3 as well. This modulator is now obsolete (at least for HD satellite channels) because DN now uses 8PSK instead of 8VSB.