sp1->sp2 needed backup and internal secondary HDDs for case of failure
 

I have data in c:/ (vista installed) Documents, Downloads etc, and also I have data to D:/ second hdd, well is dangerous after update to SP2[AND FAILURE) lost data in D:/, so backup data of it, along c:/ disc's DATA, OR NO DANGER AND BACKUP ONLY C:/ data, well? I guess the latter? ARE THEY...