The answer depends on who's going to use the device.
I personally like Debian because it has support for the prehistoric computers and of course because it was the first Linux distro to be in space.
But honestly with Linux distros it really doesn't matter what you choose, just pick one and if you find something that you don't like and can't fix because of the distro that you're on (which seems quite unlikely to ignorant me) just change distros.
Regarding lightweight, for that you should be more careful to not select a desktop environment that's to heavy. The two that I've used because they're light are xfce and lxde.
I'm currently running Debian + lxde on my Intel Atom N270 laptop, although I've been on lxde for only about two years before that I've been in xfce for probably a decade.
I don't know in what shape Kali Linux is today, but many years ago when I used it, it's main purpose was "hacking" and was quite system heavy, I wouldn't really recommend it unless you really need the tools that come with it and even that's not really a good reason since you can just install those tools on any other distro.
The distro and DE that I suggested are for really really low end old computers. If yours is more capable you could pick a more modern looking DE.
I've heard good things about Linux mint, Ubuntu is always a stable option, but yeah, just roll a dice install one and you'll see what you actually need and what you don't. I think you'll find quite quickly that it doesn't really matter what distro you're running and fall in love with the one that comes with the prettiest background image ^^.
Have fun on this wonderful journey~!