my wife ordered a Dell laptop last October, and I bought a new Dell desktop shortly after.
If you go through "small business", you'll fine more options for putting on XP, and often times you'll get a better deal.
Also, HIGHLY RECOMMEND THIS SITE WHEN BUYING A DELL!!!
www.GotApex.com
It shows all the current deals through Dell (and other companies), and gives you a direct link to the page so you don't have to try searching for deals on their site.
I just bought my mother a new Dell for Christmas (geez... like Dells much?), and got $500 off from a deal they listed on GotApex that I couldn't find through Dell.
Keep in mind, you still buy it all through Dell, GotApex just helps point out their deals. Also, Dell's deals rotate from week to week (you'll see what I mean if you shop for one long enough), so if you miss a deal, or want to wait, give it a week or two and it will be back again, sometimes better.
Hope that helps anyway. GotApex also shows deals on all kinds of other products too, but Dell is the most popular.
Also, if you want more memory, I suggest aftermarket by going to Crucial.com. Good deals and it gives you exactly the memory that works on your machine, so there's no guess work as far as memory formats, etc..
Sorry that was long winded, buying 3 computers in the last 6 months will do that to you.
Oh, and we're all very happy with our computers.
(I'd love a Mac... but just can't afford it)