The key is the aspect ratio: 1280*960 has a ratio of 4:3 and 1280*1024 has one of 5:4. CRT monitors are designed for 4:3 and not any other ratio. That's why 1280*960 is better on CRT monitors. For an example: That means that on 1280*1024 a circle looks like an ellipse. If you do not see it then don't worry about it.
On a flat screen designed for 1280*1024 (aspect ratio 5:4) the height of the screen should be a bit taller than an equivalent CRT monitor to correct the effect.
On wide screen displays there are even weirder resoltions, but most should have an aspect ratio of 16:9.
On CRT monitors all popular resolutions have an aspect ration of 4:3.
640*480
800*600
1024*768
1152*864
1280*960
1600*1200
1792*1344
1856*1392
1920*1440
2048*1536
My Matrox supports all the above and the following 5:4 aspect ratios:
1280*1024
1600*1280
1800*1440
It also supports the following 16:9 aspect ratios:
1280*720
1920*1080
And a 16:10 (8:5) aspect ratio:
1920*1200
And even various odd resolutions have been supported. Most approximate 16:9, 16:10 or 1.85:1. Others are intended for portrait page monitors. Some seem to come from thin air, but are mostly intended to reduce cost by omiting a few scanlines or to fit a block of memory convenient to the hardware/software engineers. All these resolutions exist, because hardware is made for them.
848*480
864*480
856*480
960*2400
1024*1536
1024*512
1072*600
1280*720
1280*768
1360*768
1376*768
1600*1024
BTW: Some laptops offer a 1400*1050 resolution which has an aspect ratio of 4:3.
