does dell include pci-e slots in their models?

wat about the psu, how many watts?
u cant overclock dells, rigth?
can u change the processor?
would it be better to just install an additonal gig to the gig and get 2 gigs?
would i be worthy to buy a SATA to IDE converter and install my own dvd burner?

btw im 14....money is an issue
 
-It's got a 305 Watt P/S.
-Can handle a AMD Athlon™ 64 X2 dual-core, Athlon 64,or a Sempron™.
-Factory BIOS does not allow for overclocking
-1 Gig of Memory is fine unless you want to install Vista in the future or you are doing high end graphics or video editing. Getting 2 Gigs might be worth doing now, but not necessary.
-If you already have a burner, then go ahead and just get an adapter.

Here's the link so you can decide how you want to order and how much it will cost you:
http://www.dell.com/content/products/features.aspx/cto_dimene521?c=us&cs=19&l=en&s=dhs

I hope this helped.