Flicker is typically associated with using 60 Hz under fluorescent light (BTW: I don't know that this CRT issue also applies to LCD). Chris is quite right about using the native res and refresh, so if your native refresh is 60, the solution might be to eliminate the fluorescents or at least hood the monitor. I can't think of anything other setting that would cause flicker, certainly not a change in screen res.
Of course, if you don't have fluorescents or if you turn the fluorescents off and that doesn't solve the problem, then something else is causing the flicker. Two other things occur to me purely as speculation, not from experience: some sort of intermittent fault in the backlight and some sort of power line conditioning problem. Someone with the appropriate technical background might want to comment as to whether either of these are actually physical possibilities.
> If I were to lower it .....would it make a difference as to how the edited images turn out?
Just for the record: the only effect on your output that comes to mind would be if you changed your sharpening routine because the on-screen image looked blurrier or sharper at the new res.