Hey dude, not all scripts are the same. Most will have the same features but not every script will be word for word the same. You get fun scripts (millions of popups), scripts for the more advanced users and not so much advanced. War scripts which we don't really help with on here.
We really can't tell you what would be a great script to use because although I like one, others may not vice versa so in order to find a script that you like it'd need to meet your requirements, e.g:
[*]Do you want multiple poppups?
[*]Do you want an advanced whois system?
[*]Do you want the ability to play songs?
[*]Do you want to scan the network for IRCops?
A popular script mentioned and I think (almost) everyone would agree is
NoName ScriptIt really comes down to what you like and dislike.
Here's 3 popular scripting sites:
mIRC Scripts.orgHawkee.commIRC.netAnd as always there's always the majorties or minorties favourites create a fully customizable script yourself by downloading mIRC
here.

Edit:
*Added WWW
-Andy