You'll need to get a network card in order to get on broadband which are fairly cheap.
Avast could be a good choice for either ME or XP.
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Stick with ME and get avast! Home as I run that on my 256MB RAM 500MHZ PIII system that was given to me for some service I did for a customer.
Get a Realtek RTL8169 NIC Gigabit Ethernet card from a local PC shop as they are probably less than $10.00 but you need to install the driver software for the NIC card first before you install the card.
64MB of RAM I had that on an old Win95 machine 10 years ago. RAM is going to be your biggest problem running WinXP even though Humpty says 128MB for WinXP with a bit of tweaking. You shouldn't have to tweak anything like that today, RAM is cheap if you can still get it for older machines. I bought extra RAM of eBay (512MB).
As for your anti-virus I would recommend you download AVG Free Edition 7.5.524. I use it on my Win98SE and it works and updates ok. I know there are report that they are fassing out 7.5, it should have been last month but its been extended to the end of the year.
Honestly...that computer truly isn't worth your time. It must be so dog slow, well in comparison at least, to any decent modern day system. You could always put a distro of Linux on it, something small and light, because that computer won't be good for much for than web browsing and typing documents.
Would AVG Anti-Virus Free Edition 8.0.138 work on Windows ME?
I have heard great things about AVG!
As Hazel says no it doesn't, read the technical on my link.
I wouldn't use v8.0 anyway because it has a lot of extra features which you don't need, built in antispyware.
Yes AVG is great. I've been using McAfee for 12 years without any problems but I had trouble installing the updates last year so I swapt to AVG. I did a full scan and it picked up a virus that McAfee never found.
Don't even even think about XP unless the system has at least 256MB RAM and for a Celeron processor it needs to be more.
Yeah, I wouldn't even bother putting XP on that system. I have on older system too that's been retired to a closet shelf, and to put it very bluntly and to the point XP runs like total s**t on it, it actually runs much slower than Win98 on that system.