ISO: Need help with Valentine/Cocktail Party!

Please excuse me if you read my post on the TKL Message Board. I thought I would post here when I say there is a site for party's.
We have lived in our new town for a year and are wanting to have a Cocktail party for about 100 invited guest. I have no idea how to figure how many people will come without RSVP. We thought that Valentines Day is on a Sunday so we could have it on that day, but what time? We will have pickup food but don't want it to be thought of feeding them dinner. So time? 5-7p., 6-8p., 4-6p.m.? What do you experienced one say.

Now to the food. We would like to make this a nice cocktail party using formal crystal, silver serving pieces and china sandwich plates. My oven has a warming tray that's great for keepin thengs warm and not having to cook during a party. I have a silver chafing dish bu am at a lost of what to make to use in it. I am going to make a great cheese ball recipe that has strawberry jam on top and is served with Ritz crackers, and shape it into a heart. Got any other pretty and good recipe you could share? I am open for all the help I can get. I want to serve at least 6 different things.

I plan to use my silver candlabra's on the serving table but what would you sugget for a centerpiece? I have several Magnolia trees so I can get all the leaves I need from there. Should I use my cut lace table cloth or try to get a colored one?

As you can see we want to have a nice party and just don't know where to start. Can some of you give me your idea, recipes and advice. I desperately need any help you are willing to give. We really want this to be a nice part for our new friends.

I am looking forward to hearing from all of you, I know you are endless with your creativity. Thanks so much!