Writing a VERY atypical preseed.cfg

[Richard Owlett <rowlett@cloud85.net>]

I'm doing a series installs to define my "ideal" install.
In any reasonable test procedure you change as few parameters as 
possible.
THEREFORE I make heavy use of preseed.cfg files.
I have come to the point that I wish to force manual intervention 
at *TWO* points:
  1. choice of installation partition
  2. for what purpose system is configured

The first is trivially solved.
The documentation gives a sample preseed.cfg file. Deleting ALL 
lines containing "d-i partman" will force a dialog to manually 
partition the disk.

I wish to force the menu which allows selection among 
desktop/print server/standard etc.
If you know in advance what is desired, appropriately complete 
the "tasksel" line solves. But I want o ask that particular 
question I assume my question would be answered by reading 
appropriate template file. But what udeb do I want? ???????