The "best" determines what you want to do with the drive. I personally prefer Nero, although I use many different programs.
I haven't heard of Nero slowing a system and becoming "embedded" in the OS, nor have I experienced it. In short, I think that's not true.
Nero offers a lot of control over the burning process. You can burn the disc in just about any way you want. This is why I prefer it. Its interface isn't too hard to use, but it's harder than some other programs. Fortunately, Nero Express (included with all recent versions of Nero; download the free update at http://www.nero.com
if you don't have Nero Express) is very easy to use. Nero doesn't come with many other useful programs, though.
Easy CD Creator is very easy to use, but it doesn't allow as much control over the burning process. Version 5 (Platinum) came with some other programs which might be useful, I assume Version 6 does as well. Easy CD Creator doesn't allow overburning, as far as I know.
NTI CD Maker is probably slightly easier to use than Easy CD Creator, and it has slightly more options. I believe it allows overburning.
CloneCD is only for copying existing CDs as far as I know. I don't know much more about it than that.
I hope this helped!
Edit: What CD-RW drive did you get?