Windows 8 is waiting in the wings, and while it represents a radical interface redesign, it's not all that different internally from Windows 7. According to Microsoft, and inline upgrade won't require reinstalling your apps and data. However, if you move from Vista or XP to Windows 8, or want to move to another PC, the transfer wizards move only settings and/or data, If you want to move your installed programs from XP or Vista to Windows 8, you might want to try PCmover Professional ($60, buy-only).
PCmover will transfer your OS data, programs, and settings by several means: Via network, USB, Windows EasyTransfer cable, or even external media. I opted for the network method. I transferred settings from an existing XP installation to a pristine Windows 8 installation via a network connection. PCmover must be installed on both PCs for this operation. You can install later on the destination PC and use a "mover" file created with the settings from your old installation if this is not possible.
Most of the work is done from the source PC. PCmover connects to the destination PC, makes a snapshot of the new PC, then allows you to map users, map the destination drive, filter files, and select applications. The process is easy, if not short. Check the list of programs to be transferred carefully—there may be some that you no longer need, or never used at all.
PCmover worked fine for me. Firefox, Opera, and several other programs transferred without a hitch. All my documents, pertinent settings, and users also showed up in Windows 8. I didn't encounter any programs that wouldn't run, but you should have your serial numbers handy for any programs that might require them. You can find a list of what is retained/transferred from each legacy operating system by the Windows 8 upgrade at Microsoft's site on the Windows 8 FAQ page.
If you don't want to hassle with reinstalling your applications (or you can't find the discs), PCmover is a handy, if expensive, utility that will move them over for you. However, there is something to be said for a fresh OS with a clean installation of your programs and settings … kind of like that new car smell.
Note: The "Buy it" button on the Product Information page takes you to the vendor's site, where you can download the latest version of the software.