Did I make the right purchase?

I know this is a weird question to ask, but I'm still wondering.
What I wanted was something affordable (again, this is relative) which would be $500 USD range, someting with good enough but upgradable RAM, a decent proc and good HDD. I can swap in RAM and larger capacity hard drives right away, as well as a Core 2 Duo T7300 right away. I needed this laptop to replace my hp dv9500t (which has a fried GPU ftl) and I bought this from Best Buy (i know, i know, BB isnt the best place to buy hahahaha, but I needed someting right away)

This is a Dell Inspiron i1545-4266IBU 15 inch laptop widescreen
15.6" widescreen
Pentium Dual Core T4400 2.2GHz, 1MB cache, 800MHz FSB
3GB memory
250GB HDD
standard DVD burner
standard wireless
intel x4500 MHD graphics
webcam
6 cell battery
Windows 7 Home Premium 64bit
1 yr manf warranty + best buy extended warranty for 2 years = $$$

I should mention that I do NOT game anymore, so graphcs isnt that important for me right now... however, i DO watch movies a lot and watch videos online.... as well as view lots of pics on forums (car forums).
I also multitask ALOT.... meaning with many firefox windows open (currently i have three windows, and altogether i have 38 tabs open) and i also have had 6+windows open and upwards of 120+ tabs in firefox..... as well as AIM, msword, excel, ppoint, etc etc for my research and presentations etc. Yes i Know its really excessive but that's how i get my work done.
Will this laptop be able to handle it? I have not opened the box yet, because I do not want to be charged a 50% restocking fee.

This is the first dell that I actually will own and use (the other dell I bought for my mom, and she LOVES it....)

 

The T4400 should be fine, for moderate use, probably not what you mentioned though, but maybe someone who has some more experience with this can help out. However, I have another notebook that I gave to my sister, that had a T2300 and I used that for CAD work.

 

I see, CAD work is moderately intensive.
I do have a working T7300 though that served me well. I checked and it can fit on the dell's motherboard.

 

Hey!!! Guess what everyone, Dell.com has awesome rebates on their business models!
I told my cousin about my purchase and he pointed me there.... I built a better system for about the same price. I added extras like accidental coverage, and plant a tree for me option, and faster delivery after shipping because i cant wait.
Its a Dell Vostro 1520 or something...
Tomorrow I will be returning the E1545. I hope BB refunds the whole thing and does pull a fast one instead....

The Vostro actually has a Core 2 Duo, a P7570 or whatever its called, with 3MB cache and 2.26Ghz, 4GB RAM, 320GB HDD, LED display, comes with XP with Windows 7 disk (woo hoo!!!!), 9 cell battery (i know, it will be heavy. i'll have to get a 6cell too someday), 90w charger, webcam, and its black (my fav color). Everything else is the same.