There is normally no need to change any of the sessions settings unless your hosting environment requires it (which is seldom).
The only common exception would be the "recreate session" option which most PHP5 installations have a problem with, at least prior to v1.3.0.2 where a hack was implemented to work around a php5 bug.

The defaults are:
Code:
Cookie Domain                 True   
Force Cookie Use              False   
Check SSL Session ID          False   
Check User Agent              False   
Check IP Address              False   
Prevent Spider Sessions       True   
Recreate Session              True   
IP to Host Conversion Status  true