index.dat

Hey all im kinda of a newbie so bear with me. A while back there was talk about index.dat storing urls of every website you visited and if you visit a lot of them, well then your index.dat could get very large. So i had an idea, why not delete all the urls on the index.dat.
How to. Do it at own risk:
Go to Safe Mode Press F8 while turning on Your PC
go To top of the list and click safe mode
Then log on as administrator, not your screen name.
Once there Go to c:\documents and settings\Your Screen Name\local settings\Temporary Internet Files\index.dat
Then right click openwith notepad, and delete everything in it and save it.
After that you need to right click on index.dat and click on read only so that no more urls wil get saved.
Reboot and index.dat will never save the urls.
Remember At your own risk.
You experts comment if i am wrong and if i am plz delete this forum. Thx ;-)

Forgot to mention

in order to see these files go to tools folder options and click on view then click on show hidden files and folders. Remember to log on as administrator.

after you've done this & you want windows to remember your password to your favourite forum where's it going to store the saved passwords now its a read only file ?????