Thanks for the info and well wishes Eck.
I had my good luck already
The fussy laptop runs great with Avira, and now Bitdefender also runs perfectly on this old XP-PC. I speak of the new free version of Bitdefender its very low impact, just 2 processes... and I have yet to see it reach over 160ks of memory (during signature updates or scan), and RAM can rest as low as 5kbs!
(see picture)
It's also very efficent with CPU.
The install and forget nature of Bitdefender seems to agree with old specs...