u should try the basics first
see if the controller is detected and functions in windows itself. in..
>control panel \ game controllers
or >start \ run "joy.cpl" (is just the run sortcut for the above app).
goto properties and make sure the buttons react
if not first thing id try is switching usb ports.
the faq seems to be outdated, but some of it may still apply or help point in the right direction. i wouldn't know tho, havnt used a psx emu since 1.6. the bellow quote is from www.epsxe.com/files/ePSXe_FAQ.txt
to access regedit, goto >start \ run "regedit"
yes, i know ur a newb, just don't mess with anything ur not sapose to in regedit and it won't break... navigating to the location specified by the faq if neccessary is obvious once regedit is open, im telling u how to access it because it didnt, another thing faq fails to mention is some registry settings might not take affect untill you restart ur pc.
I also heard randomly from somewhere, an emulator may have issues setting controles if denied admin access to something, for example running in a restricted user account... I don't remember what i read that about tho, or if its even true. Iv never had such an issue, perhaps it was mistakenly worded, and meant to refer to people who maybe were trying to run the emu from a folder location outside "\program files"... because even in a limited user account, "program files" has more exacution right by default but setting it up in program files requires Admin rights by default.
Code:
Q: During certain games the emulator doesn't react. Can this be fixed?
A: Yes, to get the controller working again, you just need to enable "SIO IRQ always on"
in the misc menu or simply press F4 during emulation!
Q: After I upgrade ePSXe, my controller no longer works!
A: First, make sure you are running DirectX 7.0a or 8.0a, as versions 7.0 and 8.0 have
DInput problems which were fixed in their 'a' counterparts. You can get the lastest
DirectX from http://www.microsoft.com/directx If that doesn't fix your problem, delete
the ePSXe Configuration registry entry under 'HKEY_CURRENT_USER\Software\Epsxe\Config'
using Microsoft RegEdit. After deleting the entry, reconfigure
your controller (and everything else =P) in ePSXe.