Win.XP.Pro

I can run Regi Cure and XSoft Spyware and CC Cleaner when I right click on them under Administrators sign in when I use run as.I can’t when I click on them normally.When I click on any program I downloaded it say’s I don’t have permission. I have followed directions here on changing admin.password it says I can’t I don’t have privileges.When I shut down and turn back on it rejects my password that I use to run the programs above.It says locked out.I can hit enter and get in.Can someone help me.I don’t want to have to reinstall.I have downloaded programs suggested here to help and I can’t install and run as it says I have no priv.That I am not Admin. This was set up as the Adm. for me and I am the only one to use my comp. HELP