Tovia
Whilst I would say that deleting data from tables in a non-controlled fashion is never a good idea unless absolutely necessary (and even then only on the instructions of Oracle Support), I doubt that the tables you cite are the reason for the problem.
As far as trace files are concerned, they are usually directed to the directory path asigned to the database parameter USER_DUMP_DEST
There is a way in SQL that you can see where these paths are pointing at for a given database. In SQL, do this:
SELECT name, value FROM v$parameter
WHERE name = 'user_dump_dest';
The path shown in the value column is the path on the server where your trace file will be found. Of course it is a .trc file, which tends to be a bit difficult to read. You can perform a 'tkprof' command on it to churn out some more readable output from that. Forget the syntax for that now, but if at the Unix prompt you do:
TKPROF ?
You'll get a 'usage' text which should help some.
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CT
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