I'm downloading CS:S right now. I'm curious if I will be able to run the game on it's highest settings, and if so how many FPS I will get.

My computer:

Manufacturer: HP-Pavilion
Processor: AMD Athlon(tm) II X2 235e Processor (2 CPUs), ~2.7GHz
Memory: 4096MB RAM
Hard Drive: 486 GB
Video Card: ATI Radeon HD 3200 Graphics
Operating System: Windows 7 Home Premium 64-bit (6.1, Build 7600) (7600.win7_gdr.100226-1909)

I know my video card isn't the best, but I'm hoping it'll be alright.

Yes you can.
Depends of the map but i think you get around 80-130fps in dust2 depends of the zone.

I have the pavilion 2,2GHZ and nvidia 512mb. I get around that.