How to read old non-finalized CDs

IsoBuster, CDRoller, or CD Recovery Toolbox Free might be able to read the data back off of that disc. CD Recovery Toolbox Free is, well, freeware, but not as powerful as the other two. IsoBuster has free functionality and Pro functionality that requires registration. If you burned the disc as an open multi-session disc with Easy CD Creator, then the free functionality should be all you need. If you burned the disc with DirectCD, then you'd need the Pro version.

Both Easy CD Creator and DirectCD were Adaptec products.

Finally, there's Roxio's UDF Reader -- that may also allow you to read the disc. Roxio took over the development of Adaptec's CD/DVD burning software several years ago.