is too new for Win2000 to install it and you'd need to find an older one. That's a problem though because there's a widespread pdf exploit that's out there and easily infects pdf files using older Adobe software. Just today I scanned a backup drive using ClamTK, I had windows 2000 on it previously and ran across this.
Found 26 possible threats (18365 files scanned).
/media/mint16/WIN2K-2/My Documents_Apr2010-Nov2012/WendyChiliFingerHoax.pdf BC.Exploit.CVE_2012_4148
/media/mint16/WIN2K-2/My Documents_Apr2010-Nov2012/CompaqPresario_V6105NR.pdf BC.Exploit.CVE_2012_4148
/media/mint16/WIN2K-2/My Documents_Apr2010-Nov2012/MyDocuments_Jan2007/CompaqPresario_V6105NR.pdf BC.Exploit.CVE_2012_4148
I put a few there, of the 26 problems, 25 of them were infected pdf files. They were downloaded as pdf from sites, some I'd created when I had Acrobat 4 full version installed under W2K. These were not a threat to me now, since I use Linux Mint 17 OS, but they would have been if I'd opened them on a windows system again.
About the only upgrade path for an old W2K computer today is a lightweight Linux distro. Lubuntu is a good one if you only have 1GB, or Mint MATE for 2GB system.
I don't know if current Libre Office runs under window 2 K, but it does read and allow creation of pdf files.
Oh, I just looked and seems the lowest windows is XP SP2 for Libre Office.
Foxit PDF Reader is liked by a couple friends of mine. Here's the W2K version of it, active into 2011, so not too old. Your problem is going to be making sure the pdf files are clean though.
Why not consider a current linux distro instead, run virtualbox in it, and install your W2K into a virtual drive and run it there instead? You'd need at least 2GB of RAM for that.