Windows 7 - which hard drive to buy?

I think that I need to buy a larger hard drive, as things seem to be slowing down no matter how much I cler and clean up. I have at the moment a WD Caviar Blue 500GB drive, and thought that I would get a 1TB one. I have lookad at these ones - Samsung HD103SJ Spinpoint F3 1TB Hard Drive SATAII 7200rpm 32MB Cache at ebuyer,
Samsung 1Tb Spinpoint F3 Hard Drive - HDD

1TB Samsung HD103SJ Spinpoint F3, SATA 3Gb/s, 7200rpm, 32MB Cache, 8.9ms, NCQ at scan.co.uk,

and was wondering if they were the same, and if they are any good, or has anyone got any other suggestions? I would appreciate any help as the choice out there seems to be never ending. My motherboard is ASUS P5L-Mx , do not know if that makes a difference or not

well you say the problem seems to be speed so getting a 1TB drive just doesn't seem logical unless you actually need that extra space
Unfortunate what you are experiencing happens will all Mechanical drives as the become over used and fragmented... a simple format and reinstall would bring it back up to speed
However if you looking for a speed/performance boost then i would forget the mechanical drives and go for a solid state drive
Many will look at these drive and think well they are only small ect ect but always over look the performance (ssd id the best upgrade you can buy)
What im suggesting here is for few purples extra on price of a 1TB HDD you could get a 120GB SSD, using the SSD for the OS and the 500GB HDD as a storage and installs drive
Dont be fooled over the size... bigger doesn't mean better performance

Look at my system, i run a 40GB SSD for the OS, a 150GB HDD for installs and a 500GB HDD for storage
with that selection i no longer have to go bake a cake while waiting for my pc to boot... not i hit the button sit down and surf

SSD is the way to go IMO and the prices are coming down steadily and the same for size

Here are some tests in a reputable German computer mag from last week. The first in the list (Hitachi Ultrastar) seems to be very, very fast - but not cheap. I am sure you can figure it out. Use Google translate if you cannot read German.
Testsieger 2011: Die besten internen SATA-Festplatten - CHIP Online

The Samsung 103SJ is an excellent choice. It is among the fastest drives in its class and is usually among the least expensive as well---as low as $50 when on sale in the USA.

The only thing preferable would be an SSD, but they are much more expensive per gigabyte.

I have one in an eSATA carrier as my backup drive, and it works great. It's cool, quiet, and fast.

Regarding the Samsung drive you may want to read the user feedback here. It is mostly positive, but not completly.

I have 5 Samsung Drives. They have not caused one bit of problem and are fast and cool running.

Unfortunately, with any hard drive brand, make or model, with reviews at NewEgg you will see people who claim "It's the best hard drive ever made" and somebody else will claim "it's absolute garbage"

Some people seem to have nothing but DoA harddrives, and I've never had a single 1 from NewEgg come DoA and I've probably bought 50 of them between home and work projects.

I think that I do need the space, as my hard drive is practically 3/4 full, and I regularly defrag and reinstall.

Would mu motherbaord take a SSD?

Not really sure what the diference between SSd and my Sata hard drive is

1. If your HDD is so full, you may want to consider an external disk (or if you have a desktop an additional internal disk). Those can be had for about $50 for a 500GB model. Then you can split your data.

2. An SSD is a normal Sata disk and any mobo with Sata ports will accept it. The main difference to a normal HDD is that they are unbelivably fast (access time is 150 times faster). Because of their high price, we use them only for the OS to get the performance kick. For that, a 60 GB model for around $100 should suffice.