what I did

Assuming that your problem was the same as mine -- the first hard disk was overloaded with Graphics and Music files. Since I set up everything to save to folders in "My Documents" I just copied "my documents" to the second drive and called it "main docs bkp DATE" (I use YYMMDD). Then I emptied all my folders and kept my C drive set up as always. That way all my programs & applications stayed set up and files still save to a familiar place. I back up the new "my documents" with a different name every couple months (alternating between "docs bkpa date" & "docs bkpb date") and keep my Graphics and Music files emptied out.

New games get loaded to my G & H drives (the partitions on the new disk)since they have heavy graphics. I tried changing the default save folder for my audio books the the G drive but it just got too confusing. I just like having "My Documents" do all my saving for me so I don't have to hunt.

Also BACK UP TO AN EXTERNAL media! On my second computer I got overconfident and kept a year's worth of backups only on the second hard disk. I'll give you two guesses what happened! Thank goodness I keep my financial records on a USB stick thingy.