If a speaker cable added 1 - 2 ohms of resistance would that be?

If these are 1-2 ohms, a standard good quality meter should get you close enough. Not perfect, but close enough.

No, you really need to make a four-wire measurement.  1 or 2 ohm is too much for a 8ft cable.

If the cable is 1.7 or 1.9 ohms does it really matter? The point is there is a big resistance. Even if it was 1.0 or 1.2 ... is close enough. For 8 ft it will be about 1.5.

DC resistance will affect the bass the most. It will make the sound lacking dynamic since the amp won’t be able to drive the woofer as hard.

An 8ft cable should have no more than .1 or .2 ohm of DC resistance.