If you don't need to convert to a high-res format, the trial version of TMPGEnc can do unlimited MPEG-1 conversions, which is valid on a DVD at 352x240.
If you want truly freeware, try out DIKO. (If you do that I highly suggest you go to the DIKO forums and look at the thread about using HC Encoder vs. FreeEnc as well)
Once you use either of those to convert you can author with DVD-Lab, which is somewhat limited but free for the basic stuff. A little hard to get down though.