1) Cheese platter - 3-5 large wedges of cheeses from Costco (4-5 lb total) with grapes, dried apricots, almonds, crackers & baguette slices
2) Home hot-smoked salmon platter (3lb) with mustard-dill sauce (24 oz), cocktail rye & pumpernickel (1 loaf each), diced onions & capers
3) Greek platter - hummus (2 lb), tzatziki (1 lb 4 oz), homemade sesame-eggplant salsa (4 cups), olives, pita wedges & veggies (3.5-4lbs)
4) cocktail meatballs (like the grape jelly kind but completely from scratch), made ahead & frozen, warmed in crockpot - 5-6lb meat makes 160-192 meatballs
5) penne in vodka sauce with fresh moss & basil - will make 2 pans, each 1 lb pasta & only heat 1 to start. Can heat second halfway through or freeze
6) homemade asian chicken dumplings - made ahead & frozen, steams from frozen in about 10 min, 2 lb ground chicken makes 160 dumplings
7) warm dip TBD - crab or spin-art ???
8) honey baked ham, assorted mustards/sauces, rolls (how much to get?)
9) wild rice pilaf salad with pecans & dried cranberries
10) citrus, fennel & olive salad

You are doing well on the menu, lucky guests. Here are some suggestions on amounts and tweaks.

Assuming about 30 people.

1) Cheese platter - 3-5 large wedges of cheeses from Costco (4-5 lb total) with grapes, dried apricots, almonds, crackers & baguette slices. OK, about 2 pounds bread
2) Home hot-smoked salmon platter (3lb) with mustard-dill sauce (24 oz), cocktail rye & pumpernickel (1 loaf each), diced onions & capers, ok
3) Greek platter - hummus (2 lb), tzatziki (1 lb 4 oz), homemade sesame-eggplant salsa (4 cups), olives, pita wedges & veggies (3.5-4lbs)- mostly people just look at the veg, 2.5 plenty
4) cocktail meatballs (like the grape jelly kind but completely from scratch), made ahead & frozen, warmed in crockpot - 5-6lb meat makes 160-192 meatballs, way plenty, could do just 4 pounds
5) penne in vodka sauce with fresh moss & basil - will make 2 pans, each 1 lb pasta & only heat 1 to start. Can heat second halfway through or freeze- would do 3, esp w teens there
6) homemade asian chicken dumplings - made ahead & frozen, steams from frozen in about 10 min, 2 lb ground chicken makes 160 dumplings, plenty, don't omit 3-4 cups dipping sauce, less if thin
7) warm dip TBD - crab or spin-art ???
8) honey baked ham, assorted mustards/sauces, rolls (how much to get?) 5 dozen slider rolls, and what about sliced brisket, pastrami, or corned beef instead? Much nicer surprise this time of year. About 5 pounds ready to serve. Consider quart of sliced pickles w this.
9) wild rice pilaf salad with pecans & dried cranberries- gallon plenty
10) citrus, fennel & olive salad- gallon

Desserts - I don't want to have to cut cake for 25 people so thinking cupcakes or mini bundt cakes. How many? Think I'll probably also have some candies like Hershey's Kisses, etc in silver foil (to go with the silver 25th anniversary theme).

Cupcakes are in. You could do 20 white and 20 chocolate with silver dragees to decorate the icing. Maybe all white icing with a bit of shaved chocolate added on the chocolate ones. I'm sure the guys can manage any leftovers.