Replace windows primary hard disk without reinstall?

Pity it's not Vista, one of it's saving graces is it's 'full disk backup' and restore-from-boot-cd function - worked a treat for me the one time I needed it.

You can use Acronis to image your existing drive and then clone it to your new drive. It also allows you to easily resize the new partition depending on the size of your new drive. If you don't like TrueImage, you can try other disk-cloning software like Ghost or the PING livecd.

Use your favourite imaging software like Ghost Enterprise Suite or whatnot, boot it from a disc or something. Clonezilla should do it I guess though I haven't tried its disk cloning abilities.

Have both the old and the new disk plugged in, clone the old one to the new one using a disk to disk clone (not partition). In this process you can normally resize the partitions to fit the new disk size in whatever way you want.

Shut down, remove the old disk, move the new disk to the same controller port as the old one for good measure and boot the machine.

It would be wierd if this didn't work - like the disk imaging software not really doing its job or something. As long as the disk uses the same controller there shouldn't be any problems at all.

I did it using system rescue CD IIRC. Actually any Linux live CD will do; simply use the dd command to copy the partitions from a drive to another :

dd if=/dev/<original partition> of=/dev/<new partition>