Welcome back!
I'll try to give you albums to look for where I can.
1. Blues -
Albert King "King of the Blues Guitar"
Lightnin' Hopkins "Remember Me" or "Shaggy Dog"
Robert Johnson he only recorded somehting like 20 songs.
Big Bill Broonzy
2. Country -
Somebody with more knowledge can help you with this
I always liked
Alabama, though.
3. Jazz -
Russell Malone, "
Sweet Georgia Peach
Django Reinhardt anything!
Those are just guitarists, if you want some other Jazz check out:
Miles Davis "Kinda Blue" "Birth of the Cool" or "Miles Smiles"
Art Blakey Quintet "A Night at Birdland Vols.1, 2"
Sonny Rollins "Saxophone Giant"
John Coltrane "Giant Steps" or "A Love Supreme"
Count Basie "Whirlybird"
4. Classical -
My favorite all time is
Beethoven's 7th, that's a full symphony or you could go back a few years and listen to
Vivaldi's Four Seasons, just strings.
5. Difference between Rock and Heavy Metal?
Listen to anything by the following:
Rock -
Beatles
The Who
Doobie Brothers
Jimi Hendrix
Santana
Van Halen
Journey
Bachman Turner Overdrive
Lynyrd Skynyrd
Man, there's too many... start with these and see where it takes you.
Metal -
Black Sabbath
AC/DC
Iron Maiden
Metallica
Happy Listening!
-Dave