Which is best resolutions 1280 x 800 or 1366 x 768?

Answer 1

1280x800 is a "computer" widescreen resolution, that is 16:10 (it's taller)

1366x768 is a television widescreen resolution, that is 16:9 (it's wider)

16:9 displays have started to appear on computer LCDs (both laptops and desktop displays), probably because of the fact that its cheaper (sharing panels with TVs) but also the 16:9 aspect ratio lets you sell a "smaller" panel while still advertising it as the same size (a 20 inch 16:9 has less area then a 20 inch 16:10, and side by side is noticeably smaller)

For computer work, especially coding, you should get the 16:10. The 16:9 panels are only really of interest to consumers who use their laptops for watching DVDs in the car and reading the occasional email.