How to clean slot-load drive?

I have a small issues that appears to not be software related. I am not exactly tech-savvy when it comes to apple products, thus I have had a hard time finding a solution.

Basically, I have problems ejecting discs. Firstly, no matter what method of ejecting I attempt, it will not eject fully.

After many attempts, it finally jutts out, but then gets pulled back in again. I have to contiuously eject until finally I can grab the disc and pull it out.

Sometimes running my thumbnail across the "dust flap" helps, sometimes it doesn't. When I look, it appears pretty dusty.

My Macbook Pro IS second hand. So it seems it came to me pretty dusty already.

So after all those pointers, I came to the conclusion that either the dust flap was dirty or sticky, and, maybe, the slot load DVD drive needs cleaning.

If not, can anyone point me to a permanent solution?

Otherwise, can anyone tell me how to safely clean the dust flap and/or slot load drive.