Which version of Ubuntu should I choose?

Question

ubuntu

There is a machine at work with the following characteristics:
Intel Celeron G1620 and 4 GB of RAM. The order was given to switch to Linux, I'm quite familiar with deb distributions, so I immediately chose Ubuntu, but here's the problem ... the stable version is 14.04, the latest is 15.10. There is beta 16.04, which by the way will be released at the end of April.
You can install stable 14.04.3, but will it upgrade to 16.04 without any problems? Or will it be better in 15.10 with updates? I haven't had to update Ubuntu before, but I've heard of problems with the update and for some reason everyone advises doing a clean install, but unfortunately this option will kill another working day.
Software: PHPStorm, Sublime, Chrome. Those. everything that works fine in ubuntu.
And most importantly: I would like stability, so that once I set everything up it works like clockwork.
You will have to install the system tomorrow, but I would like to receive answers today. Thanks in advance for your reply!

Answer 1

It should be easier to upgrade from LTS to LTS than from 15.10 (in theory, since the difference in distributions is greater, but it is tested more thoroughly, because many users are tied to LTS). Although in any case, problems should not arise. Set up backups for yourself and roll back if the update fails and you don't know what to do about it.

Answer 2

I wouldn't install a system that will end support in a few months. Therefore, the 15th is eliminated.
Or put the 14th if you need stability. Or the 16th beta, if there is time for a full reinstall when the final version comes out. On the beta it is written that it is not recommended to upgrade:

This release is not recommended for upgrading.