Atleast buy a 8400GS or 8500GT dude.
now yours is a piece of crap and to play CS:S u better have a 512MB graphic card to play smoothly.
Atleast if you can go for a 9400GT.
I'm not looking for the highest graphics on the game, I just want it to have playable fps on the lowest settings. I was going to upgrade my video card but only having PCI slots (I think) really sucks.
Get an 8400GS, or 5x00 or 6x00 series off of ebay and you should be able to play CSS fine. You might even be able to play older games such as Doom3 and FEAR.
Well, it will run, like a slide show. You don't really have too many options either if you only have PCI slots, for even a 8400/9400 series PCI card would be hampered by the PCI bus. If you want to play games now then you may want to consider building a computer or upgrading your current one.