My answer was for the programs, which can run without reinstalling them, like winamp, winRAR, etc. coz these programs automatically create their required registry entries when we run them in a new windows.
What u can do is just do what I told and if some programs give ERROR or don't run properly, then reinstall them.
Or do as what sakumar79 suggested, first install a fresh windows, install the programs which u need and then create an image of the parttion using Acronis or Norton Ghost. But there r 2 things which u should keep in mind!
1st, u hv to install all software on same drive, on which u hv installed windows coz u'll take backup of the windows partition.
2nd is that to make it to do work, u'll hv to first install windows and all the softwares once, then after it whenever u face some problems in windows, u can simply restore the backed up image...