So I play gunreal alot now (thanks

) and now, my FPS is anywhere from 4 to 25.
now I'm quite confused. I try turning somethings off, but I have no idea what some do.
basically, I just want the weapons, gore, and the world to be at the highest, and I could almost care less about anything else.
so what are these:
Coronas
Projectors
and Particles?
oh, my PC specs are as follows... ( It's my awesome laptop =3)
Processor:
Intel Celeron M CPU 1.7GHz
Memory:
2GBs RAM
Hard Drive:
94 GB
Video Card:
Mobile Intel(R) 945GM Express Chipset Family (224 MBs)
any help on what to turn down? or maybe its just that I'm running MSN and Xfire in the background?