Welcome to the forum!
There are a few things to check. First off, is to see if you have the "driver" (module) to run the mouse properly in Linux...
Open a terminal window and try the following command (as root):
modprobe -l | grep usb
(that's "modprobe dash lowercase-L", NOT "modprobe dash one")
You should see something similar to this:
[root][/home/my-username-here]# modprobe -l | grep usb
It's the last two lines on my output you'll hope to see -- usbhid and usbmouse. If you don't have these, then you don't have the modules available for your mouse. That doesn't mean you can't use it -- the drivers could be built-in on your kernel.
The kernel is basically the core of Linux -- in windows, this would be like having a DOS prompt only, with very limited commands, and no programs -- but you'd have drivers. When the kernel is compiled, these drivers can be built-in (so that whenever the kernel is running, the drivers are running too, all of it taking up resources) or modular (so that they're only loaded if needed and the OS takes up fewer resources this way). In most distributions, the default behavior is to have modular kernels/drivers so that there's less chance of incompatible drivers hosing a system and less resources being used, so if you're running an out-of-the-box distribution, you probably have a modular setup, meaning if you don't see usbhid and usbmouse, you may need to recompile a kernel to get them (unless there's a package for your distribution that will provide these drivers).
Anywhoo, if you DO see usbhid and usbmouse, try the following first, as root:
and it should automatically load usbmouse and any other modules that usbmouse requires. If not, there will be errors. If you get errors, post them here.
Also, there are logfiles, but we'll get to those when the time is right.