Fps booster programs are a gimmick for the lazy. All they do is shut down background tasks like anti-virus, windows update checks, Twitter feeds and and open web browsers. Any of which can easily be done by the user in Task Manager.
Apart from shutting down unnecessary running processes, the easiest way to raise fps is lower the graphics settings according to what's needed. If the gpu is struggling to keep up, lower AA, put physX on cpu (or disable it) turn down reflections/water detail etc. If the cpu is what's dragging, lower viewing distance, move physX to the gpu (or disable it), lower grass details etc. If both are dragging, lower everything from ultra to high, high to medium etc, maybe bump up character detail a notch if things start getting ugly. There's multiple individual settings that can be tailored to specific needs, play around with them till an acceptable balance is found.
If you are already at pretty much lowest settings, there's really only 1 option. Go shopping, because you've basically been outmoded by newer technology and you are trying to stay in the race... with a go-kart.