Well,,, this is a question no one can answer... because you are the only one who knows your personal taste and style.. I like the settings i did for myself but i cant say you have to try them, because only YOU know what you want..
Have a look at the first site of the screenshot thread here, there are many ENB's you can try to find what you want.
ENB's i like are from: dp3asant, icelaglace, black'd and my own (
)..... but you have to find the right settings you will like
(on gta4-mods.com you can find very many ENB's)
ps: icenhancer is a renamed ENB, so there is no difference between ice and enb (only if you dont know this)