old versions:
Click the link at the top of any page of this domain that says Download
On the left hand side of that page, it says, Release Archive. Following that link you have all prior releases available to download.
The other notable link on that page says Legacy 2.0 Branch. Click that and you go straigt to 2.0.11.
2.0.11 is safe, and supported, and ought to run fine on a server with those reqs, if my memory serves me right.
If you didnt have any trouble with 2.3.x than the latest release would be 2.3.3 -- its there, inside the release archive.