jimpierece7, welcome to the forum! Last year's best will be alright, as long as it's 64 bit. It will run on 2GB RAM, but 4GB is far better.
As far as dual or quad core, that depends on how much you want to spend. But personally, if I had to do it all over again, I would go quad core, as it's getting closer to being the standard. I'm telling you from experience, if you can afford quad core, go for it. The reason why I tell you this? There's a project that a few of us are involved in, and my dual core won't run the high performance client at the speed to get the job done. A quad won't cost that much more.
Also, it would really be a good idea to shop around. The office stores have some good deals, and so does Newegg. But, stay as far away from Best Buy as you can. They were going to charge me nearly $100 more for my desktop than I got it for at HP direct, plus all of that "geek" crap they try to sell you. If you know how to use a computer, you don't need to pay the "geek squad" $99 to set it up for you. I pulled mine out of the box, powered it on and waited for 20 or so minutes as directed, then typed in my name, address & phone #, then established my internet connection. Well, that's what those "geeks" do for your $99, except they don't do your internet connection, they don't physically setup your computer at your desk or workstation, they will sell you extra crap you don't need and install that for you, you can bring your box and garbage from the box it came in back to them and they'll dispose it for you. Isn't that nice of them?
I kept my box & packing materials in case of a warranty return. And speaking of warranties, you can get a three year one from SquareTrade for a third of the price you pay at the retailers. And if it breaks down, you are emailed a shipping label, and if the repairs exceeds what the computer is worth, they will refund every penny you paid for it. I'm living testimony to that, on two occasions. I received back $350 over a hard drive, and $185 for an internal problem where the battery wouldn't charge properly. And I have another one that is on it's last leg right now, I paid $400 for it. They pay their claims super fast, and keep you informed every step of the way.
Hopefully, my post has been of some help to you, and I hope that you find the computer that has your name written on it soon.
Best of Luck,
Cat