No, you can not use a PCI-E graphics card in a pci slot.
It is massviely lacking bandwidth for this. To put this into perspective they make PCI to pci-e x1 adapters. Meaning that the pci slot has the speed of about x1, so x16 is completely out of the quesiton.
"Will a PCI Express 2.0 x16 graphic card work on my pci slot ?"
If you are talking about a standard(old style) pci slot, it will not work.
No, you can not put a modern GPU into a decade old motherboard with only AGP slot and PCI.
In fact the only modern part (and by modern I mean made in the last 5 years) that will even interface with that board is a sata hard drive, and that will be slow as crap being stuck at sata 1 speeds.