Hope somebody can help

I am new to Linux but somehow managed to install and get get Apache
and vsFTP to work on Linux 8.

But after each day, the system seem to have error shutting down and
wouldn't again boot up.

The messages on the boot screen has quite a few "segmentation faults"
and hangs as it is doing "Enabling local filesystem quota"

When this happens, I just reinstall the system from CD again. But it
happen each day. I notice also that there were some messages about
"chron" during the shut down.

What is going on here. I am running a Pentium III with 500MB RAM.

JJ