Thank you for all your replies and I am sorry for responding this late. Why do I use Windows 2000? Because it is the best Windows version ever released and it does everything I need it to do. It performs way faster on a netbook than any newer Windows version, including XP. On top of that there is a possibility for some early Windows games on the go with Windows 2000. I also love using the no-nonsense versions of Microsoft Office like Word 95 and PowerPoint 95. Over the years I have had different Windows versions on netbooks, 7 Starter, XP Professional, XP Home Edition, but nothing works as well for me as Windows 2000. And I am not missing out on much, because Windows 2000 is pretty compatible with XP-software and drivers. I will admit though that Windows 2000 will become less and less compatible in the years to come. On top of all of this, there is something I just love to do: pushing my favorite old hardware and software to their limits.
I use a Linux netbook as well. I use it more than the Windows 2000 netbook actually, but Lubuntu really has issues with connecting to a projector properly. With duplicating Lubuntu uses only a quarter of the screen area and with extended desktop it does work better, but then I don't see anything myself. The only things that I don't like about my setups is that neither can run Microsoft Teams and neither can run web applets very well. The latter one being mostly because of hardware limitations. Luckily these are just my portable setups. At home I do all of my work on a Core i5 4th generation with a Linux Mint 19/Windows 7 dual boot.
I have considered FTP, but the thing is that I also want to be able to receive files from peers, so e-mail is really where I am at. At home FTP is a great option of course. Dual boot would be an option if I had a bigger SSD in there, but 8GB really isn't a lot. That basically leaves me two options: using another e-mail client or setting up a proxy.
I just had a look at Perdition, but I fail to find any Windows release on their website. Is there a proper Windows alternative for Perdition?
I also noticed some great alternatives were mentioned like, Thunderbird 12, Eudora and OEClassic, but because of my limited disk space, I will try first to get OE6 running. Running e-mail in Pale Moon is an option, but then I am kinda in web applet territory, which is a real pain on a VIA C7-M with 900MB of RAM (There is a 1024MB stick in there, but somehow it only sees 896MB). Even on my Linux laptop (Atom N550 with 2GB of RAM) using webmail is a pain, so I can imagine that it will be even more of a pain on this laptop.
Mimi: AMD K6-2/266, S3 Trio64, Diamond Monster 3D II, Sound Blaster CT2800, 32MB RAM
Satellite 220CS: Pentium 133, SVGA DSTN, Sound Blaster Pro, 64MB RAM
Contura 420CX: 486DX4 75, VGA TFT, Roland Serial MIDI, 16MB RAM