Need to see what I can reuse and need a $600-700 build

[Wanderer]

So I am looking to build a new PC... And I need to know what i can reuse from my old PC to save money (Will hopefully be building this by christmas) I live in USA Arizona.

This is what i currently have:

[url]http://reviews.cnet.com/desktops/gateway-gt4022-media-center/4507-3118_7-31975712.html?tag=mncol;psum[/url]

Replaced PSU with [url]http://www.newegg.com/Product/Product.aspx?Item=N82E16817182031[/url] (fairly recent)
Added 1 gig of RAM (This was a long while ago)
Don't want to reuse mobo becuase it is failing, the main reason why I am building a new PC.
I have mouse, keyboard, monitor, and speakers that are reuseable.

So what can i reuse with a $600-700 build?

I want this to run games fairly well (Fallout 3 high, WoW high, etc.)

[AncientGrandpa]

Can you reuse the dvd/cd drive?

Here: [url]http://secure.newegg.com/WishList/PublicWishDetail.aspx?WishListNumber=8041529[/url]

[JohnEdwards]

wait till you got the cash