Well, I couldn't quite decide for all of them, but here are my answers:

1. The Bangles or The Buggles?
Battles

2. The Go-Gos, The Goo Goo Dolls, or Kajagoogoo?
The Go! Team

4. Crosby, Stills, and Nash ... or Crosby, Stills, Nash, and Young?
(La Monte) Young

6. Sheryl Crowe or Counting Crows?
Cromagnon

7. Counting Crows, Culture Club, or Cutting Crew?
Crystal Castles

8. Poison, Prince, or Police?
Ponytail

9. Sting, Seal, Styx, Shai, or Shanice?
Sole

12. Bad English or Modern English?
Hrvatski

13. REM or EMF?
AFX

14. Mr. Big or Mr. Mister?
Mr. Nogatco

16. Earth, Wind, and Fire ... or Blood, Sweat, and Tears?
Peter Bjorn and John

17. A-Ha, N-Sync, or O-Zone?
µ-Ziq

21. Al Green or Al Jarreau?
Albert Ayler

22. Billy Ocean, Idol, or Joel?
Bill Evans

25. The Turtles, The Monkees, The Byrds, The Penguins, or The Eagles?
The Dodos

27. Three Dog Night, The Four Seasons, Five For Fighting?
Six Organs of Admittance

29. Percy Sledge or Sister Sledge?
Robert Sledge

30. Sister Sledge or Sisters With Voices?
Palace Brothers

33. Wang Chung or Chumbawamba?
Chihei Hatakeyama

34. Conway Twitty or Carmen Twillie?
Aphex Twin

35. Rednex, Yello, Green Day, or Shades of Blue?
White Williams

36. Vangelis, Vengaboys, or Ventures?
Vapnet

37. America, Europe, Asia, or USA For Africa?
Manitoba

38. The Romantics or Love Affair?
Love

39. 4PM or PM Dawn?
The One AM Radio

40. The Cars or Cab Calloway?
Busdriver

41. Stevie Wonder or The Wonders?
Ray Wonder

42. Frankie Lymon, Valli, or Jackson?
Frank Zappa

43. Bobby Darin, Day, Brown, or McFerrin?
Bobby Hutcherson

44. Coasters, Contours, Crests, or Crystals?
The Curtains

45. WHAM, Slash, Smash Mouth, Smashing Pumpkins, or Crash Test Dummies?
Boom Bip

46. Firehouse or Crowded House?
Beach House

47. Y&T or C&C Music Factory?
MV & EE

48. Naked Eyes or Talking Heads?
The Flaming Lips

49. Queen or Ben E. King?
Bonnie 'Prince' Billy