I'm looking for (relatively) lightweight KDE distributions. My parents have an older, dust-collecting PC that I'd wish to salvage. Without spending money on upgrades, I think the situation calls for linux.

Out of the linux desktop environments, I think KDE is the most intuitive/best fit for their needs*. Does anyone have distro recommendations?



*The run-down:
My dad knows how to browsing on the internet and listen to music.
My mother doesn't know how to do much of anything on a computer.
My sister is tmh (trainable mentally handicapped).

in general to keep things light turn off composting (desktop special effects) and desktop indexing (nepomuk and strigi)

you will get better performance using a desktop kernel instead of the default (usually more server orientated) if the distro provides multiple kernels (such as openSuse does).

i'd just use what ever distro you're comfortable with and select light weight apps if cpu and ram are an issue

once installed and tunning you can check cpu and ram usage using the system monitor app

I have to say debian stable, if you are okay with kde 4.4.5. Havent tried unstable yet.

I managed to get a 110 MB ram on startup, of course with no compositing and strigi turned off, but with nepomuk on , korganizer daemon on.

It was really a wow situation to find out that you can get more functionality out of a desktop than any other linux DEs can give you ,yet consuming less memory .

give your specs.

for light music players look at look at xmms2 and qmmp

Arch!

Give a try to Chakra. Also, disabling desktop indexing and effects will increase your performance a bit.

Another vote for Chakra. It's a KDE-only distro, so there will be no GTK libraries occupying memoryspace during runtime, so theorethically it should be fastest. My personal experience says so, too.

Another for Chakra.

The first thing I look for when I load up by new distro is how efficient the CPU usage is using the 'top' command in Konsole. I've tried this with all the major KDE distro's and noticed Chakra to be the most efficient on my system with Sabayon to be a very close second.

I can get Chakra to the point where it hangs at 100% idle CPU and only drops to 99.9% once in a while. I only used the advice above and my advice below to do this. I could never achieve this low CPU in any other environment (Gnome, Xfce, lxde...).

To save CPU you can also turn off sound notifications (knotify4) if you don't need it. Personally I find notifications get in the way most of the time:

System Settings -> Applications and Systems Notifications -> Manage Notifications -> Player Settings -> Choose "No audio output"

The next time you log in it will be turned off.