Differin is a low strength retinoid so it will do both but it wont happen over night. I would just use the Differin at least to start with. You dont want to aggravate your skin and cause it to break out leaving you with more red marks. Just see how your skin looks after a couple months.

Differin works by increasing your skin cell turnover. It may bring up existing acne from under the skin so your skin may get worse before it gets better. I use it in combination with BP wash and clindamycin to treat the breakouts as they occur.

I wouldn't use hydroquinone. It's dangerous and could bleach the skin around your red marks, leaving them more stark and apparent.