Is the CPU/VIDEO combo enough for my needs?

Hello,

I'm looking to see if anyone has an opinion regarding the following system I noticed on the Costco web site.

http://www.costco.com/Browse/Product.aspx?Prodid=115388...|84|90366|56670|78129&N=4045270&Mo=65&pos=0&No=18&ViewAll=66&Nr=P_CatalogName:BC&cat=78129&Ns=P_Price|1||P_SignDesc1&lang=en-US&Sp=C&ec=BC-EC10590-Cat56670&topnav=#

Intel I5 450m 2.4ghz, 4gb ddr3 mem, NVIDIA GeForce GTS 360M with 1GB GDDR5 discrete graphics,
500gb 7,200rpm sata, Microsoft Windows 7 Home Premium (64-Bit)

The Costco computer I have found above seems to have most of the items I am looking
for. I could look forever and with each and every advancement I would just keep
wanting more. So it's time to make a decision. [/b]

Things I feel that are important to me are as follows:

Speed of the computer in doing the tasks I have listed below. I have been reading about
the I7/I5 notebook comparisons on the forums and am up in the air regarding this. I feel
that if I get the i7 720qm branded notebook I would be running into heat issues where the
I5 450m would be just as fast and last me for the next 4 years of computing.

My budget is about $700-$1000, I would like this computer to last me for 4 years or so.
Size would be desktop replacement so maybe 17"
Not sure about screen resolution. I probably would destroy the native resolution
and opt for a resolution that would have larger print. (my eyes are old and tired!)
I would like to get about 4 hrs of battery life.
I do not play games, may try some day but not important at this moment.
I would like at least 500gb media storage preferably at 7200rpm.
Not sure which OS platform I would like, Probably win7 but I may load my old xp-64
version or perhaps Ubuntu on it.

Tasks I’d like to utilize the laptop for.

a) DVD Shrink for encoding home movies onto DVDs.
b) Nero for writing DVD's (have a super old version, I think around 6.02 and it does all
I want)
c) WinRar, Winzip for compressing files/folders.
d) Adobe Photoshop elements for video encoding. I am currently using an AMD dual core
Athlon x2 3800+ processor and it just is not very quick. I would like to get the most speed
for my buck in this category.
e) Ripping my music cd's to mp3 or other formats.
f) I would like to use AutoCAD light program for work and will be working on multiple
2-3 mb excel files at one time


Thank you for your suggestions and for such great information on the forums.

-Paul