Hi there!

The lower limit of normal is actually 20 million/ml with 2 ml volume= 40 million total. So you are on the lower limit of normal with that. The grade of motility I find confusing. My DH had one sample with a 2.5 grade and one with a 2 grade. From what I've researched anything with a 2 or less is not really moving forward, just kind of "wiggling". But I'm pretty sure that doesn't mean that NONE of them are moving forward progressively, just not very many.
So I would say there is some room for improvement, especially with the motility, but to be honest...your DH's number's look awesome compared to alot of our DH's on here. My DH and I have a 20-month old son (took us about 6 months to conceive) and have found out while TTC #2 that DH has a sperm count of 3.2 million/ml with 36% motility.
I would get your DH on a good multivitamin with plenty of zinc, selenium and folic acid and have him take at least 1000mg of Vitamin C a day. That can help with the motility. L-carnitine also helps with motility. If you are interested, a few of us have our DH's vitamin regimines listed above under "Infertility Tricks" up above. I definitely think it is very possible to get pregnant with counts like your DH's though