There isn't a best script, they are all better for different things. The most popular (but not necessarily the best) ones seem to be "Invision", "NoName Script" and "Tracer Script".
Quote ParaBrat:
The best script is the one you write yourself..it does exactly what you want, no more, no less
a word of advice, use caution in what third party scripts you use, unless you can understand EXACTLY what they do, dont d/l them. some websites check their scripts for backdoors, most dont.
