Ok, so dell is out. Between the two config u have given, the 1st one is a beast. U will soon understand why they r giving 12 cell battery instead of 6. Pentium 4 with 17" screen with X600 card !! everything will squeeze ur battery like anything...It will heavy too. But if u r going to work static and generally power-plugged, then its okay.
The biggest negative point with the 2nd config is Athlon. Although athlon rules the roost in desktop section, intel is far superior in lappie section. I am very sure soon amd will catch intel up, but till now, its intel who reigns. Acer ferrari has come up with athlon 64 bit, but I heard that even after that the performance is not worth of the money spent.
My advice is that, u go to
www.notebookreview.com and search laptops after giving specific config set.