Choose any of the 48 Preludes & Fugues from The Well-Tempered Clavier (24 in Book I, 24 in Book II). You might wish to listen to a few before finding one that you like and have something interesting to say about.
Here is the link to the Robert Levin recording via Columbia University Library.
You also might want to compare Robert Levin's performance with Angela Hewitt's performance on piano. It could be much faster or slower, as Bach did not write tempo markings for these pieces.
The link to the Liner Notes in the upper left-hand corner of each might help start you off. Be sure to cite them if you use them.
Warning about the Levin recordings online: All of the Preludes and Fugues are unfortunately mislabeled and misordered. Consult the table below and be sure to cite the correct BWV (catalogue number for all of Bach's many works).
Book I | Book II | ||||||
Wrong BWV | Right BWV | Number | Key | Wrong BWV | Right BWV | Number | Key |
846 | 858 | 13 | F♯ major | 870 | 882 | 13 | F♯ major |
847 | 859 | 14 | F♯ minor | 871 | 883 | 14 | F♯ minor |
848 | 860 | 15 | G major | 872 | 884 | 15 | G major |
849 | 861 | 16 | G minor | 873 | 885 | 16 | G minor |
850 | 862 | 17 | A♭ major | 874 | 886 | 17 | A♭ major |
851 | 863 | 18 | G♯ minor | 875 | 887 | 18 | G♯ minor |
852 | 864 | 19 | A major | 876 | 888 | 19 | A major |
853 | 865 | 20 | A minor | 877 | 889 | 20 | A minor |
854 | 866 | 21 | B♭ major | 878 | 890 | 21 | B♭ major |
855 | 867 | 22 | B♭ minor | 879 | 891 | 22 | B♭ minor |
856 | 868 | 23 | B major | 880 | 892 | 23 | B major |
857 | 869 | 24 | B minor | 881 | 893 | 24 | B minor |
858 | 846 | 1 | C major | 882 | 870 | 1 | C major |
859 | 847 | 2 | C minor | 883 | 871 | 2 | C minor |
860 | 848 | 3 | C♯ major | 884 | 872 | 3 | C♯ major |
861 | 849 | 4 | C♯ minor | 885 | 873 | 4 | C♯ minor |
862 | 850 | 5 | D major | 886 | 874 | 5 | D major |
863 | 851 | 6 | D minor | 887 | 875 | 6 | D minor |
864 | 852 | 7 | E♭ major | 888 | 876 | 7 | E♭ major |
865 | 853 | 8 | E♭ minor | 889 | 877 | 8 | D♯ minor |
866 | 854 | 9 | E major | 890 | 878 | 9 | E major |
867 | 855 | 10 | E minor | 891 | 879 | 10 | E minor |
868 | 856 | 11 | F major | 892 | 880 | 11 | F major |
869 | 857 | 12 | F minor | 893 | 881 | 12 | F minor |