Program to winner my pc?

I run XP and I was wondering if there is a freeware program to lock my pc while I am away or does XP have this feature?

 

I mean program to "secure" my pc from usage

Disable fast switching in User Accounts in the Control Panel and apply a password to your user account.  This should enable you to hit CTRL-ALT-DEL and lock the workstation when your not in front of it.  This is the feature in XP.  Never needed anything outside of that, so I don't know of any 3rd party software to do that. 

 

The only problem is if you have other accounts created, they just have to turn it off and log in as themselves or use there own profile...