I have a Inspiron 537s Slim Desktop with about 3 or 4 slots available for graphic cards or upgrades in general. What parts could I use to play the latest games? Any Suggestions?

I would like to aim more at the Nvidia brand.

http://accessories.us.dell.com/sna/productdetail.aspx?c=us&l=en&s=bsd&cs=04&sku=a6116820

Don't bother with that lol, a) Terrible Brand (PNY not Nvidia) b) Terrible video card

Whats your budget?

At the moment, I don't pay any bills and when I get a job, I'll have a few hundards in my hand with in a month.

Well, first make sure you can fit these by looking at the demintions but basically its:

780 - $500 = zomfg max everything 60 fps 1080p or higher

770 - $370 = max everything 60 fps 1080p (higher in most cases but not all)

760 - $260 = max a lot of things and 60/30 fps on a lot of things (mostly 60 fps on stuff thats not dx11) and 1080p on a lot of things but not the really high end stuff

750 TI - $190 = max some things and 60/30 fps and 1080p, can't really max high end stuff

Least thats what I think that is... All those are provided your computer itself isn't a bottleneck such as the cpu and you can fit those cards into your PC. Also make sure the powersupply is compatible with the video cards and dell PCs usually come with custom made powersupply that you cannot replace or else the motherboard doesn't work (least thats what I heard)... Anything below that its not usually worth buying

Also, as for companies, I recommend Asus and MSI for GPUs