We know what replacing the C drive a with a bigger drive means - loss
of all installed software AND Dlls.
just to add to what rundll already posted... yes, it can be done without loss of
data. throw the new drive onto the secondary ide channel and partition and format
it. then copy everything from c: to the primary partition of the new drive (you can
do it with windows explorer). then put the new drive in place of the old c:, boot
with a startup diskette and make the primary partition active, reboot, and everything
should be fine. ive done it before.