Time Machine won't Replace Safari HELP!!!

Ok, I've been having problems lately with Safari. It has become
increasingly unstable. It was crashing several times a day then
the latest update helped to only get safari to crash once every
couple of days.

Well, Safari finely crashed and it won't launch without crashing
a millisecond after appearing on the desktop. So I decided to
restore a more stable Safari from Time machine. The problem
is, Mountsin Lion won't let Time machine delete the troublesome
version from the Applications folder. I get a Message which states
something like " Safari can't be deleted because it is a System
Application".

So, how do I get Time Machine to do its job and Restore
an earliry more stable Safari?

Thank you!!!!!!

 

My Time Machine captures of Safari were
also corrupted.

This is what has seemed to work. I'm using
Safari to type this. First of all it is unlikely
that Safari is damaged but is probably
a support file so I restored Safari to its
initial state by dragging to my Desktop
these Safari folders:

~/Library/Safari/
~/Library/Preferences/com.apple.Safari.plist
~/Library/Caches/com.apple.Safari

This forces safari to rebuild these missing
files on relaunch.
Then I launched a Virgin Safari. It launched
for a millisecond then crashed. @#%&* so
I though I would send Apple a message.
When an App. crashes the Application Crash Report
Window appears. I typed some nasty comments
and dragged them into the Crash Report Window.
My intention was to Launch & Crash & send my
nasty comments to Apple ALL AFTERNOON
over and over again while I watched TV.
Yes, I know, cool........... I'm frustrated
through no fault of my own. Anyway, after
about the twenty fifth or thirtieth crash
Safari stopped crashing........go figure.
I quickly updated two Clones. So thats where
I am right now. So far everything seems
fine.