Windows 7: Specs for a new Win 7 / AutoCAD Laptop, input welcome

I've decided to retire my desktop and get a nice desktop replacement system. Use will include normal web browsing, some light gaming, and home media but the primary purpose will be running CAD programs.

I was looking at some name brand, in the stores systems but nothing appealed to me. I've also been displeased with most of the big names at some point in the past. I have a friend who is a tech, that can get me a Nexlink machine (made by seneca). I'm looking @ a machine w/ the following specs:

core i7 proc
4 or 8 G ram (I'm heavily leaning toward 8)
1G graphics card with DVI and HDMI out
250G 10,000 RPM HD.

It will have win 7 pro on it.

For the same price as the above, I can get a 500G 7500RPM HDD. 250 seems small to me if I end up wanting video, etc. on the laptop. However, the 10,000 over 7500 RPM thing is nice. What way would you guys go? Right now my buddy is seeing if he can get it with a 10K RPM drive larger than 250G.

Also, considering what RAM costs for these things, I'm assuming I should just go 8G right off. What's normal, and who is happy with how much you have?

Once I solidify the HDD & RAM (RAM I'm pretty sold on 8G) I'll have it on order. Then it's just whatever I should have to take care of it. I'm thinking padded bag, wireless keyboard & mouse... anything else? Should I have a sort of desk w/ fans under it if I want to use it sitting in bed? Anything else I'll want to consider?



This is going to be my first laptop and my first system build for Win 7, so if there's anything I'm not considering that I should be, please speak up!

Thanks,

Dan