Just Ordered my 17R few question

Ok so a few days ago i sold my Alienware M15x it had the I7-720 8 gig of DDR3-1333 a 500 gig 7200 HD full HD Screen
and alot more i just never used it it had been a year since i utilized any of the Hardware fully that i actually got it for
so i decided it was time to go so i sold it for 1275 on Thursday nite

I decided that the replacement will be a new Inspiron 17R
I know im heading from a Ferrari Enzo to a Buick Lacrose
so i know not to expect as much form it as i would if i where gaming but im curious about a few things

from Dell they only offer a Upgrade to 6 gigs of Ram the guy who bought it pinched me for every pany on my old system so i only gave him 4 gig so i kept 1 of the 4gig DDR3- 1333 so will this work in the new Inspiron 17R ? also will i actually be able to use all 8 gigs if i put this in or will it only utilize 6 of them ?
oh i did purchase it with only 4 gigs because they wanted an exta 60 for 2 more gigs i could get for 25 at microcenter
so will i be able to utilize 8 gig if i put this 4 gig in or will it down clock to 6gigs ?

also i got the 2nd gen i5 how will this be compared to the first Gen I7-720 i had i know im going from a quad core to a dual core i believe but will i really notice much of a change ?

also they only offer the inspiron with the 5000RPM HD i had the 7200 with the free fall sensor so what will i notice with this can i upgrad to a 7200 ?
or even a SSD or is there no point in putting an SSD or a 7200 in a Inspiron ?

Below are the specs of the system i got i paid 774 for all of it i think thats a great deal
but did i get a good set up or should i change it ?
1 225-0976 Inspiron 17R
1 317-6289 2nd generation Intel Core i5-2410M processor 2.30 GHz with Turbo Boost 2.0 up to 2.90 GHz
1 317-6296 4GB, DDR3, 1 Dimm
1 320-2071 17.3in HD+ (1600 x 900) LED Display with TrueLife
1 421-3642 Basic Stage
1 320-2053 Intel HD Graphics/HD Graphics 3000 with up to 1.6GB Dynamic Video Memory
1 342-2280 500GB 5400 RPM SATA Hard Drive
1 318-0471 Exchangeable Lid (WLAN) - Diamond Black (BLK)
1 318-0392 Windows Live Wave 4
1 331-0806 Windows 7 OS Label,CNB
1 331-1534 DELL RESOURCE DVD,BACK-UP,N7110
1 421-5780 Genuine Windows 7 Home Premium 64 bit Service Pack 1, English, No Media
1 420-6436 PC-Restore, Dim/Insp
1 420-6576 DELL WELCOME,Software Dimension/Inspiron
1 420-7938 Dell Connect 2.1
1 420-9691 DataSafe Local BackUp
1 420-9876 Cozi-Calendar
1 421-0092 DELL-DOWNLOAD-FLAG
1 421-0757 Skype VOIP Application
1 421-2086 eBay Webslice
1 421-4047 Dell Digital Delivery Client, version 1.0
1 421-4118 WHITEPAGES.COM,Webslice
1 421-4289 Dell Support Center Software 3.0
1 421-4586 TRUSTED-ID,ICON
1 421-4587 JAGEX,WEBSLICE,ICON
1 421-4588 NEXTJUMP,WEBSLICE,ICON
1 463-2282 Dell Owners Manual installed on your system,click on icon after system set-up to access
1 430-3605 Integrated 10/100 Network Card
1 410-0548 Adobe Acrobat Reader
1 318-0425 8X Tray Load CD/DVD Burner (Dual Layer DVD+/-R Drive)
1 421-4541 Roxio Creator Starter,No Media
1 313-8545 High Definition Audio 2.0 with SRS Premium Sound
1 430-4154 Intel Centrino Wireless-N1030, 1x2 bgn (2.4GHz) + Bluetooth
1 421-3874 Camera Software 2.X, Factory Install
1 331-2332 English Documentation,Inspiron N7110
1 331-2333 Keyboard, US
1 331-1894 Power Cord,125V,1M,C5,US
1 331-2321 Shipping Material, Direct/Touch/Non-touch
1 410-9461 McAfee Platinum, 36 Month, MUI, Fast Track
1 312-1179 48 WHr 6-cell Lithium Ion Primary Battery
1 410-0487 Microsoft Office Starter: reduced-functionality Word and Excel with ads. No PowerPoint or Outlook
1 939-5640 Dell Hardware Limited Warranty, Extended Year
1 939-5650 Dell Hardware Limited Warranty, Initial Year
1 939-5690 Dell Limited Hardware Warranty Plus In-Home Service After Remote Diagnosis, 3 Year Extended
1 939-5660 Dell Limited Hardware Warranty Plus In-Home Service After Remote Diagnosis, Initial Year
1 950-7447 4 Year Limited Warranty
1 980-5878 Accidental Damage Service, 4 Years
1 412-0358 Soft Contracts Consumer Accidental Damage Agreement
1 420-8878 Soft Contracts Dell In-Home Hardware Agreement
1 900-9753 Warranty Support, 3 Year Extended
1 960-2780 Warranty Support, Initial Year
1 988-0099 To activate your online backupaccount, go to Start, Programs, DataSafe Online
1 927-2357 DataSafe Online 2.0 2GB
1 421-4356 Software, DataSafe Online 2.0 2GB

 

For the i5 you will notice a difference if you play games, general usage probably not so much. SSDs will benefit any system and yes..it will accept the 8GB.

 

if i get back into games again
what will i notice ?
from what the dell rep explained the 2nd gen I5-s should be up there with the performance of the first Gen i7 wich im not sure i get because its dual core and the i7 was quad core