If you've experienced trouble with your old hard drive, forget what I'm about to say here--you'll just end up copying bad data (including a corrupted OS) to your new HD.
Ok, having said that, if you're just upgrading to a newer, larger HD, and want to easily copy EVERYTHING, including Windows, to the larger one, first, go out, and buy a new one (yes, @Best Buy, or sometimes Office Depot or Staples has the 'best deals'), with this in mind:
Your laptop will only recognize a maximum of 120GB of space, so don't buy any larger (160GB and up) or they will all only show 137GB for your boot drive (although you can still accept that, and once done, merely download this freeware
to create a new partition and use that as if it were another drive 'D:').
There are now only two major reputable dealers--Western Digital and Seagate ('cause Seagate bought out the third biggest, Maxtor, years ago).
Hard drives are one of the most justifiable new purchases, because 100% of them come with better hardware warranties than the ones do if you bought a brand-new laptop right now!
Seagate often sells theirs with a full-on 5-year replacement warranty, and Western Digital sells none with less than 3 years, so the $50-$100 you'll spend is more than worth it in a laptop.
Now, for the reason--those new HDs all come packaged with a software disc with Acronis' 'True Image' software, which will do all the work for you, perfectly, the very first time, as long as you follow the on-screen directions, and have the 'new HD' plugged in to your current laptop as an external drive--for that, you'll have to have a laptop IDE to USB enclosure (as in this link
). They have 'em at Best Buy, but much more $$, I saw $39 online, so ...cheap may be fine, esp. if you only plan on doing this once!
Anyway, the software does the rest, immediately reading up that you have a new drive connected (after you install the CD), and actually asks you if you want to copy it (and you do).
It then performs a sometime lengthy bit-to-bit copy (you're legally required to kill off the old one or never use it again, by Microsoft's standards, remember)...and you're done--new, larger HD, with all your data AND Windows OS on it!
NOTE: Sometimes this process requires that you reboot once again into your old hard drive with the new one still attached, to finish out!
Once this is done, you turn off your laptop, remove it's battery, then replace the old hard drive with the new one. If you've never done this, it's a lot easier than you'd think--Dell still offers this little method online at the following link>>>>>>>>CLICK HERE
See? Not hard at all!
Once you're done, and start the laptop back up, you'll see it act like it doesn't even know the difference, except you have more drive space.
Remember to download that freeware above (Partition Wizard) if you bought a drive larger than 120GB, because you can then make a new 'data' partition and use it to the max of that actual drive!