Win XP, 2 installs

I recently change a HDD for a friend. The new HDD has Win XP, I wouldn?t let me boot up, so I tried Repairing XP with no success, I reinstalled XP into a diferent folder.. C:/windows2. I still can?t load up into the origional version of Xp, how can I repair it and boot into the 1st version? Since that is the version with all the programs installed into it…etc…