I looked up your meter and did not see an R1 setting.
http://www.sperryinstruments.com/documents/products/dm-4100a.pdf

Lowest setting I see is 200, this scale will read from 0 to 200 ohms.
Set it to this scale.
Note the reading, this is what you get with infinite ohms (open).
Now short the meter leads together, you should see a 0 or something like 0.00 etc. This is a dead short.

A couple things to watch when measuring ohms and continuity
1. Always remove power from the machine otherwise you could blow your meter.
2. Always disconnect at least one side of any device you are checking. This eliminates the possibility of measuring an alternate/parallel circuit path.
3. When checking for closed contacts and continuity use the lowest scale (Usually 200 ohms). Then try higher scales. This scale is 0 to 200 ohms so if the device you are measuring is 300 ohms this scale would show an open circuit which it is not, you are just measuring outside the scale's dynamic range.

There is a good STICKY at the start of this forum about it's use.

You are welcome

Hopefully your unit is now up and running.