I'm getting the Acer Aspire V3 (http://www.newegg.com/Product/Product.aspx?Item=N82E168...) and from reviews I found out that the 5400RPM hard drive wasn't very good. I'm not sure what to look for in a hard drive other than total gbs and RPM, or if it will even be compatible. I just want to know what makes a hard drive compatible and what hard drive would help to improve this laptop (preferably under $100).
Find a 2.5" form factor 750gb or less with 7200RPM spindle (the 1 tb's are sometimes too tall for laptops). NewEgg to hard drives, select those components then start doing some comparisons/review readings.
Also, look at the Seagate Momentus XT (750gb new version). It's hybrid and getting some good reviews, but is about $125-150. The 500gb is under $100 but doesn't have near the performance of the 750gb.