All possible value of datatypes are mentioned in the API:
http://paramquery.com/pro/api#option-column-dataTypestring, stringi, integer, float and date
Both date and datetime fields are supported, they have common dataType = 'date'
Since pqGrid depends upon jQueryUI for date formatting, time formatting is not supported.
For time formatting, you could do it yourself or include some other library.
---Edit--
The bool dataType was missing from the doc. It's been updated.