Originally Posted by oncdoc
Ive been messing around with the program and only God knows what IVe done. Can I set everything in terms of conversion options to default some how?
Calibre saves its settings in *.py files. You must delete them while calibre isn't running and they will be recreated with the default settings.
For an English Windows XP, you'll find them in "C:\Documents and Settings\<your username>\Application Data\calibre\conversion". Other systems, searching for "*input.py" should put you on the right track.
(Calibre is multiplatform, so it's always a good idea to specify your OS when asking questions.)