Laptop buying advice forum: New Laptop ASAP HP DM4-1160US(i5) vs Toshiba L645-S4059(i3)

I bought a $1500 Dell Latitude Laptop w/Intel Core Duo 2 but after 2 yrs it's running slow & won't hold a charge. Need a new laptop & looking at these two: *I am not tech savvy, I just want a laptop for grad school that will last about 3 yrs. PLEASE HELP!! (price diff between HP & Toshiba is $80)

http://www.staples.com/HP-Pavilion-dm4-1160us-14-Laptop/product_904965?storeId=10001&jspStoreDir=Staples&cmSearchKeyword=hp+dm4&fromUrl=home&langId=-1&catalogId=10051&cmArea=SEARCH&ddkey=StaplesSearch

Toshiba Satellite L645 S4059 Laptop Computer With 14 LED Backlit Screen Intel Core i3 370M Processor With Hyper Threading Technology by Office Depot

HP Pavilion
* Intel? Core? i5-450M Processor (2.40GHz)
* 4GB installed memory
* 500GB hard drive
* SuperMulti 8X DVD?R/RW with Double Layer Support
* 14.0" diagonal High-Definition HP BrightView LED Display (1366 x 768)
* Brushed aluminum finish with the stream design in argento
* HP TrueVision Webcam with integrated digital microphone
* HP SimplePass with integrated fingerprint reader
* Wireless LAN 802.11b/g/n WLAN & Bluetooth? with WiDi
* 5-in-1 integrated Digital Media Reader
* 101-key compatible with island-style full-size keyboard
* 6-Cell 55WHr Lithium-Ion Battery; Up to 7 hours of battery life
* Genuine Windows? 7 Home Premium 64-bit
* Dimensions 13.42 in (L) x 8.98 in (D) x .098 in (min H) / 1.27 in (max H) (4.41lbs)
* 1 year warranty

Toshiba Satellite
* Intel Core i3
* Extra-large 4GB memory lets you run your most demanding programs.
* 320GB hard drive holds thousands of songs, photos and documents.
* Wireless-N for high-performance, cable-free networking. Lets you access wireless networks to share files, surf the Web and exchange email. Can provide improved range and speed within a Wireless-N (802.11n) network, and is also compatible with 802.11b/g networks. Wired networking is supported, too.
* 14" diagonal LED-backlit TruBrite? screen. LED backlighting permits a thinner and more energy-efficient screen.
* Plays and burns CDs and DVDs.
* Memory card reader for fast, easy photo transfers. Transfer your digital photos, music and other files from 5 types of memory cards.
* Built-in webcam and microphone let you keep in touch with others via video and voice messaging.
* Face recognition software, for hassle-free logins. Securely access your computer and accounts without typing passwords.
* Provides up to 5.8 hours of battery life on a single charge.
* Microsoft? Windows? 7 Home Premium 64-bit. The newest version of Windows makes everyday tasks simple.