Since you gave me generic parameters, my generic answer is right now Vista is not fully supported hardware/softwarewise so I would wait until the official public release or one or two months beyond that.
Since you cited your mouse and video card, those will work for sure right now. However, if you have anything extraneous like a PDA or printer, you may want to make sure it will work, Microsoft has a Vista compatibility wizard you can download and it will tell you.Compatibility Wizard.
That'll tell you what works and what doesn't for sure. Even though it says some things may work or some of your programs are iffy, more than likely there will be Vista patches for it, so don't freak out.