Online Documentation
Oracle
Long text
Converts to (N)CLOB - long text will convert to CLOB or NCLOB datatype.
Converts to LONG - long text will convert to LONG RAW datatype.
Converts to (N)VARCHAR2 - you can convert such columns to standard (N)VARCHAR2 types, but be aware that maximum length of VARCHAR2 column is 4000 characters, while maximum length of NVARCHAR2 column is 2000 characters.
Data loading
This choice is available only in Enterprise. Editions are able to use Standard insert statements only.
Standard insert statements - slow and compatible mode
Use APPEND hint - add hint to Oracle to always insert above (and increase) high watermark area to avoid looking for space and speed up inserts.
Internal fast Full Convert loader - Full Convert can take advantage of Oracle fast loading mechanism to achieve more than order of magnitude speedup.
Use DML array instead of direct path - Sometimes, direct path loading, although speedy, has limitations that can get in a way. In that case, use this option.
Misc
Preserve table and column case sensitivity - use double quotes when defining table/column names in order to preserve the casing.
Skip primary key creation - if your source tables' data does not conform to the defined PK, use this option not to create PK.
Parse views as tables - sometimes you have access only to a certain view, not to full table. Use this option in that case. Enterprise only.
Create sequences and before-insert triggers for identity columns - emulates native identity fields of other databases by creating sequences and triggers. Sequence start values are calculated to begin on the next natural value based on current data in the table.