Are you certain you want to do this?
The added security of XP Pro is only really of importance to corporate machines with a lot of data requiring the extra security or for paranoics who think that everything and everyone is trying to steal their information.
I am not suggesting that you are paranoic but there are easier ways of securing anything that genuinely requires it.
To answer your question, though. No, I'm pretty certain you cannot use XP repair to install the upgrade.