Paint Chips
mrtram: as requested, here are my suggested BenMoore paint chip numbers (which also have names now). Keep in mind that an internet photo is a bit more difficult to work with, so you might want to get some of these chips from your local Benjamin Moore store and look at them at home as close to the roof as possible. I also strongly suggest taking a photo into your paint store to see their suggestions as well. Now for the chips:
2112-40 (stone) - 2 base
2125-30 (gray shower) - 3 base
CC-450 (caramel apple) - 3 base
HC-69 (whitall brown) - 3 base
HC-76 (davenport tan) - 3 base
Hc-106 (crownsville gray) - 3 base (might be the best bet as it has a touch of green it it and will help distract greatly from the roof)
Also, please be cautious about the sheen of the paint (flat, eggshell, pearl, semi-gloss, gloss) as the higher the gloss, the more the green of the roof will be reflected in the paint on the house. Try to go with an eggshell or pearl (preferably in oil) to reduce the reflection.
You might also try getting a few painters to come in and offer you quotes, with their suggestion for paint colours. Great thing about most painters is they'll give you colour suggestions during the quote process and then you don't have to use them, but have got some free professional advise on colours! I always offer free colour consultation with quotes. Good luck on the painting, and don't forget to get some nice high green bushes or trees near the house to help pull the eye away from the roof.