can applications and data under 32 bits OS work under 64 bits OS?

the OS of my PC is ubuntu 12.04 32 bits desktop. i want to convert it to 64 bits desktop. i plan to do a backup of the /home/username folder, then do a clean install of ubuntu 12.04 64 bits desktop, then copy across the previous /home/username folder (32 bits) to the new 64 bits OS, can the 32 bits applications and data in /home/username folder work under the new 64 bits OS?

 

Not sure - some might work, but I guess you will also see a lot of errors.

 

the data shouldn't matter IMHO. 32/64bit is only for applications and how the cpu processes them I think.