I have a Dell Dimension 4600.
My computer ~ Properties tells me I have:

A Pentium4 3.0Ghz processor,
512mb of RAM,
And what I think is a 64MB nVidia GeForce4MX 420 graphics card.

I can smoothly run a game called Vietcong, a relatively old FPS, with not amazing graphics. And I can run Morrowind fine. Also Counter Strike: Condition Zero.

I don't want to spend $30 to find out I can't either of them. (CSS, Gmod)

As you can probs tell I'm not too computer savvy, So I'm really looking towards you guys for help.

Thanks, and let me know if you need me to upload more info about my junkpile.
I guess you could just look up Dell Dimension 4600 specs on google, though.

Your cpu is fine, more ram would be better, and your videocard def needs a upgrade. You CAN play css and such but with everything turned down to the max.

I hoped that would be the case, Thanks WJ.
Also, What video card is suitable for me? (Cheap, Easy)

Knowing that videocard can come in both pci and agp slots, that would need to know, also what store can you buy from so i can pick something they have

The model of his motherboard would be much, much easier to get.

If I were you I'd use CPU-Z to check your motherboard model number. There might be some alternative way, but this is a useful tool nonetheless.

Download: http://www.cpuid.com/download/cpuz_147.zip

Launch it, go to the "Mainboard" tab of it, and tell us what it says next to "Model". For instance, mine is MCP61PM-AM.