I'd up the drive to blu ray if you think you'll want it but it's £90 so take ur choice (easy enough to upgrade later).
Contact Dell and make sure they put in one of the decent GT-555M chips. There are two different sorts and one is substantially better than the other:
http://www.anandtech.com/show/4475/a...-summer-2011/3
(You want the B version with the extra cores)
Stick at 1920x1080 screen but I wouldn't however select the 3D screen as SFAIK this means you can't have Optimus which is far more valuable in my book.
IMO what you want is the 3D capable GPU since it's the higher spec but to have optimus enabled on the laptop. Quite why they can't get optimus to work at 120Hz is annoying, (perhaps the onboard IGP isn't able to sustain 120Hz?)
I would also upgrade the CPU to i7-2760. It's got more meat to it, better
cache* and various other features
IIRC (compare cpus here
http://ark.intel.com/compare/53476,53474,53469). No need to go to i7-2860 that isn't worth the extra
IMO - unless they have it on a mega offer or something.
Also check out
www.dmxdimension.com - they give links to dif base config codes you can use AND then also use the voucher code at the top of the page to get a further % off.
Oh, and good luck finding a carry bag for it - if Dell offer you one take it take it take it. I have a nightmare lugging my 17" laptop around.
* sorry not better cache, but supports faster memory, virtualisation and other features plus it has a faster clocked IGP which is definitely desireable IMO