Hey! I have Nankang tires!

heheh. and I like them. A lot. Sadly. They're like cheap Kumho's...if there were such a thing. Gotta love the performance, look, and feel at this price.
I believe they had a test on 17's vs. 18's in Road and Track a few years back. Between 16, 17, and 18, the 17's were best all around in wet weather, dry weather, track, and drag. 18's are only good for looks but 17's are best for all around performance on normal cars. I think that for your gen accord if it's a '91, then I'd go even lower with the 16" rims.
Don't get me wrong. I think 18's will look really nice though, and I hope you don't plan on racing in them. I believe most 4th gens run 17's though. Not that it should matter what other people think. It's your car. Personally, I'd stick with the 18's if they don't rub. 2" drop seems like a lot though (maybe because I have a kit with 1.5" drop).