Hi Dianne, welcome to Garden Web, and Merry Christmas.

1. This one will be tough. First of all, most of the very tall OG's, that will survive your zone, require full sun. Second, they will only provide a screen for part of the year. They need to be cut to the ground in Spring, and don't reach full height until the summer. During that period, you won't have a full screen. You might want to consider Conifers for the screen. There are many that will achieve that height in your zone, and do not need full sun. They also will be evergreen, providing a year-round screen. You could also consider Hollies and some varieties of Euonymus.

2. So many choices here! There are probably thousands of OG's that will thrive in this area, ranging from only a few inches tall to ~4 feet. Woodland grasses like Luzula's and Deschampsia's. Chasmanthium latifolium. Many Carex varieties.

I suggest you hit the library or bookstore, for a copy of Rick Darke's The Color Encyclopedia of Ornamental Grasses, to get an idea of what options you have, what they look like, and what they require.

N. Sea Oats, Chasmanthium latifolium, does very well in shady conditions. I planted mine about two years ago, and they reached about 3-4' tall last summer.

I also have some Miscanthus "Adagio" that has thrived in a fairly shady spot. It get strong sunlight around midday for several hours, but shaded in morning and late afternoon. It forms a mound about 2-3' tall.

Good suggestions so far. Some cultivars of Miscanthus sinensis do tolerate partial shade; the best of these for that condition are: M.s. 'Variegatus' and 'Gracillimus' (the latter does fine for me with only afternoon sun). 'Adagio,' as noted, is okay, and I have read that 'Strictus' will take a bit of shade. Miscanthus 'Purpurescens,' ("Flame Grass") will do okay too, but it will not take on its fiery fall color.

Partial shade for grasses still means at least 3-4 hours of direct sunlight with bright shade the rest of the day. As far as full shade, don't waste your hopes; even Chasmanthium struggles there, perferring partial or very bright shade; the same for Deschampsia, although the more sun it gets, the better it performs. Calamagrostis brachytricha ("Korean Feather Grass") grows attractively lax in [bright] shade. Check out the Hortiplex pics (linked to this site) for the grasses we've mentioned, or do yourself a bigger favor and get Darke's book, as Donn suggested.

As far as deer are concerned (a big problem for me too): they don't touch the grasses. But in winter, they will eat whatever is available, even toxic plants like rhododendrons (as you probably already know), so evergreens, not a preferred food in summer, would have to be protected from late fall to mid-spring in z6a. The dried foliage of grasses if browsed will be cut back come spring, anyway.

Good luck.