It depends what kind of script you have if it's a standalone one that doesn't need anything else then no you won't need a CMS, but if it is a script for a CMS then you would need to install whichever one it is for. If you need more specific help either e-mail me:
[email protected] (replace the 0's for o's) or contact me via my icq in my sig.
Hope this made some sense
Rob