Root Will 'Factory Restore' truly replace my modded OS with its original??

[HappyJoe]

I want to sell my Hero, which currently sports a 2.3.4 Elelinux mod, so think it might be a good idea to restore it to its last kosher HTC kernel.

Will 'Factory Restore' from Settings be enough to do this unaided? If not,
will running (how, I have yet to find out) my copy of 'recovery-clockwork-2.5.0.7-hero.img' do this?

Alternatively, since I want to pass on a clean machine without any real problems - what might be the most stable and unsurprising alternative to install?

 

[DonB]

I will move your post to ATR section to get a better answer, but I believe you will have to run the RUU.exe to get back to Stock, or if you did a Nandroid back of your stock ROM when you rooted you can restore that