Hard Drive Copy

I'm looking for a reliable, sure way of copying hard drive to hard drive. This includes: Operating System, Registry Files, EVERYTHING. I want to be able to switch my hard drives and have it act as if it were the original except with more space.

A little more in depth explanation:
I was given a 300gig hard drive for Christmas, so now I want my 40 gig HD(Has the OS on it) to transfer onto the 300 gig. I have a 150 gig HD in my computer currently, but I want that to stay as a storage drive. I'm going to hook up the 300 gig drive where the 150 is right now. Hopefully transfer EVERYTHING from the 40 gig HD to the 300 gig hard drive, Operating system and all. Then use my 300 gig in place of my 40 gig and put my 150 gig back where it originally was. It is VERY important that the Registry Files and the Operating System are copied.

I'm asking if anyone has had any experience with any HD copy programs and has had it work perfectly fine. If possible, I'd like the program to be free, if it's not, show me anyways. Right now I'm looking at a program from Norton called "Ghost". It seems like it will work, but I don't know if it will copy the OS and Registry files.

Thanks for your time.

Okay, so I made a huge mistake when using Norton's Ghost. It worked PERFECTLY. I mean everything works. It works just the same as I had it. Problem is that it's only 40 gigs. Yay! 40 gigs only of my beautiful 300 gig HD. :( I know what I did wrong though, there's an option that says to fill up all the unallocated space, and I didn't know what that meant until now. So if anyone plans on using Norton Ghost in the future, you need to use that option...now to format, and re-copy. Woohoo another 4 hours of waiting! <3