Here are some commercials that aired during The New Batman/Superman Adventures:

1. Math is Power PSA
2. Chicago White Sox VS. Mariners Baseball WGN promo bumper
3. Full House syndicated promo bumper (Weekdays at 5:00pm on WGN!)
4. Animaniacs End Credits
5. Amblin Entertainment/Warner Bros. Television Animation (1996)
6. 'Batman' will return after these messages
7. Pert Plus for Kids
8. Double Stuf OREO
9. Post Pebbles Cereal's BedRock Rocks
10. Men in Black: The Series Kids' WB promo
11. Batman Beyond Kids' WB promo
12. Now, back to 'The New Batman/Superman Adventures'
13. 'The New Batman/Superman Adventures' will return in a moment
14. Wrangler Jeans
15. FritoLay's Planet Lunch Packs
16. NesQuick
17. Pokemon Kids' WB promo
18. The Big Cartoonie Show Kids' WB promo
19. Full House syndicated promo (Today at 5:00pm on WGN!)
20. Dudley Do-Right TV trailer
21. And now, back to 'Batman'
22. (same as #13)
23. Tiny Toon Adventures & Histeria! Kids WB promos
24. 7th Heaven The WB promo
25. Christian Children's Fund
26. Chicago Cubs Baseball WGN promo bumper
27. 'Superman' will be back in a moment
28. (same as #16)
29. Pringles
30. Post Oreo O's Cereal
31. Pokemon Fever Kids' WB promo
32. (same as #24, #12 & #13)
33. Old Navy
34. M&Ms Mini's
35. (same as #9, #10 & #11)
36. Pokemon: Adventures on Orange Island? Kids' WB promo
37. (same as #20)
38. Richard Simmons' DreamMaker WGN promo
39. And now, we return to 'Superman'
40. (same as #12)
41. Histeria! Kids WB promo
42. Animaniacs Kids WB promo
43. Monster Ballads CD Soundtrack
44. Be A Mentor PSA
45. (same as #2)
46. The Parent 'Hood WGN syndicated promo
47. Hawaii Five-O syndicated promo bumper (Weekdays at 1:00pm on WGN!)
48. Split-Screen Credits
49. Warner Bros. Television Animation (1997)
50. WGN: Entertaining America Station ID (1998)
51.

Video footage courtesy of munichmarvel and AnimeDude892 (Stuart) at archive.org
All credit of this footage goes to them!!