I just finished my migration to LinuxMCE and wanted to write this down someplace, hope it helps someone.
Hopefully you did a backup and saved the files from /myth/backup.
After you have MythTV working (able to watch TV) you can restore parts of the databases you want to keep. For example to import your `oldrecorded` table.
gzip -d mythconverg.sql
grep -n "DROP TABLE" mythconverg.sql
1186:DROP TABLE IF EXISTS `oldfind`;
1207:DROP TABLE IF EXISTS `oldprogram`;
1228:DROP TABLE IF EXISTS `oldrecorded`;
1271:DROP TABLE IF EXISTS `people`;
1294:DROP TABLE IF EXISTS `phonecallhistory`;
1319:DROP TABLE IF EXISTS `phonedirectory`;
sed -n '1228,1270 p' mythconverg.sql > oldrecorded.sql
mysql -D mythconverg < oldrecorded.sql
The first sed number (1228) is the line matching the table we want, the second (1270) is -1 of the next table.
Repeat for any other tables you want to import.
If you had any tv shows recorded you can import them as well. Move the files into the /home/public/data/tv_shows_1 (or tv_shows_0 not sure the difference but this worked for me) directory and import the 'recorded' table. Then restart the mythtv-backend.
Not sure if it was needed, but in the logs it yelled at me so I ran:
for each in `ls *.mpg`; do mythcommflag --file $each --rebuild; done
inside the tv_shows_1 directory as well.
oldrecorded = shows recorded in the past
recorded = shows currently recorded
record = shows to record