The manufacturer of your harddrive has software which will migrate everything that's on your present hard drive to your new one.
For instance, here is Maxtor's:
MaxBlast 4 is a one-step, ATA/IDE hard drive installation utility. MaxBlast 4 makes hard drive installations and upgrades hassle-free for novices and professionals alike by automatically identifying, partitioning, and formatting any IDE hard drive, making it data-ready in about one minute. This version of MaxBlast is used on systems with already existing Windows installations to copy all your data to the new hard drive in order to use it as a boot drive, or additional storage drive. If you're building a new system, the MaxBlast bootable floppy or CD versions are recommended.
* Easy to use Windows interface
* Compatible with Windows 98, Me, Windows 2000, and Windows XP.
* Breaks the 528 MB, 2.1 GB, 4.2 GB, 8.4 GB, 32 GB, 64 GB and 137 GB capacity barriers.
* Supports both FAT32 and NTFS drive partitions.
* Supports up to four ATA devices in the same system.
* The copy feature lets you make an exact duplicate of your existing hard drive.
* Fast ATA and Serial ATA compatible.
* The installation tutorial option allows you to view the installation process before physically installing your Maxtor ATA hard drive.
Note: There must be at least one Maxtor ATA Disk Drive installed in the system for MaxBlast 4 to run.http://www.maxtor.com/portal/site/Maxtor/m...s&downloadID=58
Other manufacturers provide similar software.