screw brand name. they will only screw you with parts that can't be upgraded.
get a computer friend and go to
www.pricewatch.com
select the "pc's with windows" in the first section and take your pick. you can upgrade them all right there with pricing that changes as you select your different components. Go to a discount computer store and get yourself a monitor, speakers, and a mouse-keyboard combo and you will be set. You may pay a little more initially than going to dell because of the monitor and stuff. but in the long run, you will enjoy it much more. My brothers dell only lasted for a year and a half. then i had to buy all new internal components so he could upgrade it. thats how they make money, by skipping out on upgrade features. make sure you motherboard has 3-5 pci slots. everything else should be picked for you.
ECS and microtech boards are in the "ok" category. If you want it to last a while get an Asus or Intel board. they are sturdy reliable boards that have always been great in my PCs.
*I would be more than happy to help you with getting your computer together. if you are interested, PM me and let me know what your gonna use it for and what you want to spend, and in the next couple of days or so, i can put something together for you and send you a link to it so you can take a look.