I've just installed ADF_Blitzer and got it working fine. I used the menu to select DF1 (you'd probably want DF0 - but it's probably selected anyway). I clicked "Write", selected the ADF, and it happily wrote to the disk in DF1. At what stage do you have problems? If for some reason you cannot get it working, I'd again suggest that you try a simpler prog like ADF2Disk.
Don't worry - Amiga is usually far easier to use than windows; it just takes a bit of getting used to. A lot of people have problems with ADF's, LHA's and disks at first, and they're usually easy to diagnose by someone who's been through them ;-)