Lubuntu is a good operating system for many old computers, but not for all of them. Some computers have too little horsepower or memory. A rule of thumb is that the computer should not be more than 10 years old.
Memory (RAM)
For advanced internet services like Google+, YouTube, Google Drive, and Facebook, your computer needs at least 1 GB of RAM.
For local programs like LibreOffice and simple browsing habits, your computer needs at least 512 MB of RAM.
Processor (CPU)
The minimum specification for CPU is Pentium 4 or Pentium M or AMD K8. Older processors are too slow and the AMD K7 has problems with Flash video.
These are maintained by the Lubuntu team.
run dialog called from one desktop opens on the desktop with preferences dialog, regardless of which desktop is current (1445818).
ALL DESKTOP IMAGES NOW REQUIRE A DVD OR USB.
Cursor invisible after timeout and screen-saving (1572640) and possibly (1568604).
All images require a DVD or USB. As a workaround, use the server or netboot images.
Thanks to the hard work from our development team, these bugs have been fixed in the 16.04.1 milestone:
Abiword language selector text cut off in abiword (1484785).
Abiword always starts after logging in (1432271).
Abiword icon has extra smaller icons included (1586708).
Intel video driver not installed by default on Lubuntu 16.04 fresh install (1575460).
Missing Lubuntu Plymouth logo (1582046).
Pcmanfm crash on invalid path (1562764).
Head over here to get it.
3 years support (until April 2019)