You're going to need some patches and updates. Luckily a complete madman in Japan has refused to ever leave Windows 2000 to this day and shares his work with the world at Windows Legacy Update
Old sources will tell you to install Opera 12. While Opera is the best for pure compatibility, it's completely unusable now because of the web's silly insistence on TLS everywhere. You'll actually need two browsers because some pages will crash one and vice versa. The first is K-Meleon, the second is Retrozilla (this link may crash k-meleon and won't work on either. You'll need to bootstrap this from another computer.)
Honestly notepad pretty well sucks. Notepad++ as far forward as 6.6.6 works fine.
I believe emacs....20 also supports 2k, but I haven't set that back up.
For pictures and similar you're looking for IrfanView, the classic. 3.97 is the magic version. For videos, DVDs, and the like there's VLC, where you'll want 1.1.11
A bit of a catch-all, but: you won't have access to ssh as it won't negotiate protocols correctly, but you can use PuTTY versions as new as 0.61. For FTP you're looking at 3.0.11.1 of FileZilla. The only working mail client I've found is OE Classic, which explicitly continues to support Windows 2000.
You'll be spending a lot of time on abandonware and old versions sites. Major Geeks and Old Version will be some of your best friends.
If you find yourself needing a website which just won't load, throw Frogfind at it and see if it'll work. If you just need some stuff to look over in general while you're bored there's always the Directory too.