The Acer 3003LCi (costs about $599 or less depending where you get it, Circuit City, Tiger Direct, etc) notebook would probably fit your bill, and the AMD Sempron processor is pretty quick, is cheaper and would beat most of the Celeron 1.4 GHz notebooks that are out there.
I want to buy a notebook with following specifications.
Intel Celeron 1.4 or above (yes Celeron! As I need low priced), 256-512 MB RAM, 40 GB or more HD, 15 or 15.4 inch screen (matt or glossy whatever). Should be from Acer, Dell, Compaq, Toshiba, IBM or Fujitsu.
Only work I like to do with it is internet surfing and using Microsoft (or Open) Office. Also I intend to use it to present Lectures on Power Point via a Projector.
Which model you suggest for me.
Also can I use it to present some educational videos via a projector during lectures? It is of course not a must requirement for me.