Well a quick view over at NewEgg
shows about 60 video cards that they sell for PCI slots. So now it comes down to how much you want to spend, and if the Dell supplied power supply can work with the card. Now according to the documentation you only have a 230W PSU (Power Supply Unit) in there. That isnt much. Being a Dell there isnt to many options to upgrade the PSU either.
From what i seen on all the cards that you said you needed, they require a larger PSU. So you are going to have to find some way to upgrade your PSU to at least 300W in order to get a card.