Glad it appears to be working out for you

For future refrence the section O2 in the Hijack this log is reserved for BHO or Browser Help Objects such as toolbars, this however can be exploited to change your home page and to throw up adverts etc.
If you look at your section O2 it has description related to what each BHO does, in general nasty ones have no name such as O2 - BHO: (no name) the example you had while the other BHO's you have show information related to the Yahoo toolbar which you are either running or have had on your system at some point in time.
Obviously because I could not identify what the file auyftt.dll was I could not offer definitive advice on the matter other than to state what I personally would do from experience.

if you find that the browser has lost any features that you use then it may be related to the BHO which you have backed up and removed -- I doubt you will get any problems though