Well, buying the RAM elsewhere is cheating

, but I was looking at the first one on your list, the E6410 (your simultaneous post focused on the E5410/5400). The E5410 currently has a deep discount, so I wondered if it isn't a runaway winner in terms of bang for the buck?
Oh... Yeah, the E6410 is a lot more money. However, even including the cost of the RAM from Newegg an E5410 system is still under $800.
I haven't talked to my Dad since I gave him the suggestions, but I will follow up with him and try to push him to the Dell over the HP given all of the comments here. I think the Lenovo is just out of the range of what he wants to spend.
Here's the Dell Latitude E5410 I have spec'd out:
PROCESSOR: Intel® Core™ i5-520M (2.4GHz, 3M cache) with Turbo Boost Technology
OPERATING SYSTEM: Genuine Windows® 7 Home Premium, 32-bit, no media
(May re-install the system with the x64 version)
LCD PANEL: 14.1 inch Wide Screen WXGA Anti-glare LED Panel
(may get the WXGA+ if he wants it)
WARRANTY & SERVICE: 1 Year Limited Warranty and 1 Year Mail-in Service
EXPANSION SLOT AND MODEM: Express Card without modem
MEMORY: 1.0GB, DDR3-1333 SDRAM, 1 DIMM
(buy 4GB from someone other than Dell)
CAMERA/MICROPHONE: Digital Microphone
(don't think he needs or wants a webcam)
PRIMARY STORAGE: 160GB 5400rpm Hard Drive
(HD upgrade options from Dell are too expensive, and it can be upgraded easy enough later)
OPTICAL DRIVE: 8X DVD+/-RW w/Roxio and Cyberlink PowerDVD™, no media
WI-FI WIRELESS CARD: Intel® Centrino® Advanced-N 6200 802.11a/b/g/n Half Mini Card
BATTERY: 6 Cell Battery
PRIMARY POWER OPTIONS: 65W A/C Adapter (3-pin)
Cost: $675 + 4GB of DDR3 RAM (~$110)