I need help on buying a laptop.

I'm going to buy a laptop with my tax check. I have a budget of $1600.00, that has to cover everything S&H etc. I've been looking at two different Toshiba laptops. Here are the specs. they are both customized units.
Satellite A300-ST6511
Intel® Core™2 Duo Processor T9550 (2.66GHz, 6MB L2, 1066MHz FSB)
Genuine Windows Vista® Business Bonus (SP1, 32-bit version) XP
Microsoft® Office® Basic 2007*
4096MB PC6400 DDR2 800MHz SDRAM (2048MBx2)
15.4" Diagonal Widescreen WXGA TruBrite® display (1280x800)
ATI Mobility Radeon™ HD3650 with 512MB DDR2 discrete memory
+ up to 255MB allocated shared graphics memory
400GB HDD (5400rpm, Serial ATA)
400GB 2nd HDD (5400rpm, Serial-ATA)
DVD SuperMulti (+/-R double layer) with Labelflash™ drive
Intel® WiFi Link 5100AGN (802.11a/g/n)
No Bluetooth (No Antenna)
Lithium Ion battery (6-Cell, 4000mAh)
1 Year Standard Limited Warranty
Laptop Price as Configured: $1,494.75

Laptop#2
Intel® Core™2 Duo Processor T9550 (2.66GHz, 6MB L2, 1066MHz FSB)
Genuine Windows Vista® Home Premium 32-Bit
Microsoft® Office® 2007 Basic Edition*
4096MB PC6400 DDR2 800MHz SDRAM (2048MBx2)
17.0" Diagonal Widescreen WXGA+ TruBrite® display (1440x900)
ATI Mobility Radeon™ HD 3650 with 512MB DDR2 discrete memory
+ up to 255MB allocated shared graphics memory
400GB HDD (5400rpm, Serial ATA)
400GB 2nd HDD (5400rpm, Serial-ATA)
DVD SuperMulti (+/-R double layer) with Labelflash™ drive
No Bluetooth (No Antenna)
Lithium Ion battery (6-Cell, 4000mAh)
Laptop Price as Configured: $1,479.75

Toshiba has free shipping till the end of March. That's not a big deal but it does lower my cost. The Laptop with the 15.4 screen comes with XP downgrade, which makes it cost more than the one with the 17" screen.
I like XP, because I'm of the understanding that Vista sucks. I've never used it, is this true? I reallized a fact that I hadn't considered, after reading somthing on this forum. Does the T9550 run hot? What happens to a laptop when it over heats? Does it mess up anything ie. the OS? I'm not a big gamer, but I'm wanting to run Chessbase 10;Fritz 11; That's not to say I would'nt like to play the new version of Red Dawn 40K online. What do you guys think?
Gen. Romulas OUT!

Thank you so much! Your the only one out of 56 people who cared to help me. I looked at the Sager AWSOME! However, What's an Intel Turbo-memory module, and should I get the 4 gig or 2 gig?