Best Backup Program

I am looking for recommendations on the best backup program available.

My workstation is currently running XP PRO/SP3, but may eventually
upgrade to Windows 7, so compatability with both is a plus.

I would like the ability to mirror my main c: drive to a bootable
external drive.

I would like to be able to backup an entire internal or external drive
to a different external drive.

I do not plan on backing up to DvDs or optical disk.

Being able to backup individual directories/files would be a plus.

Compression is unimportant. My external drive is 1TB & I have 150 GB
internal capacity. I'd prefer to have a plain vanilla backup - that
is I'd be able to use Windows Explorer to view the backup & retrieve a
file if I choose.

Quality, reliability, and ease of use take precedence over cost. If I
can not accomplish what I want with one program, multiple programs are
fine.