I don't think you'll have much trouble putting the card in, and while it isn't a high end card, it isn't bad. If you're not going to be playing graphics-intensive games with your rig, this card should serve you well. I've never been a big fan of Dell, they make mediocre rigs and then back them with terrible customer service. They don't upgrade easily, and if you do upgrade them, I'm certain that Dell won't honor your warranty.
At any rate, I'm not bashing your rig, just Dell for being so greedy. I hope you have an easy, troble-free upgrade. Oh, and in closing, drop at least another 512mb of RAM in that rig, you'll be glad you did.
I\'m already visualizing the duct tape over your mouth...