I would recommend Dell also. I just bought one for my Mom-In-Law about a month ago. P4 2.3GHz, 17" flat panel display, WinXP Home, 512MB, DVD, CD, 40GB HDD. Paid around $1k shipped. I set it up for her and I was surprised with how quiet it is. You literally cannot hear anything when it is on. If the monitor wasn't displaying the XP desktop I would have thought it wasn't turned on it was so quiet. It is a decent system-much better than the Pentium 166 she was using until I bought her this setup.
I don't know how they are for support because I've never had to use their support...Wait, actually that's not true. I bought a refurbished Dell flat panel display and tried calling Dell customer support on a Sunday. I kept getting some guy who sounded like he was from India on the phone who was absolutely no help. I ended up calling the place I bought it from to RMA it. They sent me a new unit for the same price and credited me shipping costs there and back.