Mind being more specific? Ty!
WSE is Warband Script Extender which is developed by cmp. WSE2 allows for a number of things that you cannot do with the first script extender.
Some of the features:
Better graphics
Icons in the log, not just text
Specific controls like "drop shield" (at least I think it is only a WSE2 option)
ect.
I recommend you use it, since some things might be out of sync or wrong when you are playing on the WSE2 server (EU_1, 2, 3).