Installing CrapCleaner

To expand on this so CZ14B827 has an idea, yes you can set CCleaner to delete all the items it cleans with algorithms that secure file erasers use, to do this ( and yes its slower depending on if you use a 1 pass or 7 pass )

In CCLeaner goto Options > Settings and under secure deletion click Secure File Deletion and then in the drop down menu pick the erase option you want 1 pass, if your very paranoid on the data could be recovered if someone had right software, but 3 and 7 passes will be near impossible to recover the data.

But 1 pass would suffice if your pc is not about to be picked up by the FBI or NSA ( enter some other security agencies here also ) and all you want is a quick deletion of the index.dat and one that a index.dat reader wont recover.