Omni is right, have it catered, so you do not have to do all the work. And find someone to do a killer cake, all silver and pretty, or do a replica of the original, in original colors, or this time in silver.. A buffet is always good, and less expensive than a sit down dinner. Serve the food you can afford, a hot meal, sandwiches, hors doevres, or serve the meal the parents had. .
You could do an open house thing, where people drop by and wish them well, or do an by invitation, sit down party.
If you can't afford the movie thing that omni suggested, , have an album of their wedding pics [make sure you use copies, so you don't ruin anything precious], or blow up some pictures of their wedding, you could put several on posterboard, or pick a nice one, and put it on a heavy backing, or find a frame and display it on an artist's easel.
Try to invite the original wedding party, and honor them with a silver corsage or boutonniere if they show up and it doesn't have to be expensive, you could make them yourself]. Have a lovely corsage for your Mom, and a boutonniere for your Dad.
You could have the 25th in the colors of the wedding, or with some silver touches, or go all silver. Try the local party store, they can help.
You could get a band, or a DJ, or bring a CD multidisk player, and play the music they had at the wedding, or what was popular 25 years ago.
If you are having alcohol, make it champagne, and make a lovely toast. This could be your brother's moment to really shine. Tell the story of how the parents met, how they are the best parents ever, how grateful you both are that they are the best.
Be sure you and your brother stand in the reception line with your parents and welcome everyone, or if you are not doing that, both of you make rounds, and introduce yourselves, and thank everyone for coming.
If you are doing favors for the guests, there are lots out there, my mother bought glasses, and put a 50 gold sticker on each one for a favor for my grandparent's 50th. A little siver box with chocolates, a Hershey bar with a custom wrapper, or find out from your Mom what her favors were at her wedding, and duplicate, if it is cute or possible.
Our party store is loaded with cute favors way under a dollar. Little plastic swans, cakes, brides and grooms. And has lots of the honeycomb fold out decorations for the table and whatever, custom balloons, anything I could think of for a party. If you are crafty, do your own decorations! the party store sells rolls of paper for tablecloths, and custom print napkins, and has 25th ones prepackaged. Ours has a full party rental service, rents tables, chairs, popcorn machines, punch bowls, chocolate and champagne fountains, glasses, arbors, you name it.
Check your local printer, or Hallmark, for invitations, and ask at the post office if they have special stamps that say love on them.
And raid your family's keepsakes. Someone might have a wedding program you could make a copy of, or have saved a napkin, or an invitation. Cute idea to duplicate somehting, or have it on display[again, copy it or protect it someway so it will not get ruined]. and make sure you have a big decorated box for cards, and see to it that it is guarded.
The only thing I do not suggest doing, is a money tree. I personally do not like them, I bring a present, and there is the tree, I feel like I should put something there, too, and I feel Ishouldn't have to be made feel that way, enough is enough on spending . One over zealous tree tender just insisted I put some money on it. She saw me bring in a gift. Most people who give money would just as soon put it in a card. Some people think they are obligatory, and if you don't have one, someone will notice. Keep some envelopes hidden, the card box guard can offer one and a pen if someone is in distress over the lack of a money tree. and again, have a card box guard, someone to say thanks! when a card is dropped in is a nice touch. If family won't, maybe your brothers best friend will do it, for the offer of a free meal and cake. Your brother might need some moral support from a friend, but if he is really close to the family and has someone near his age, might not be necessary.
Nice touches are to have someone man the coffee pot, cut the cake and serve it, these could be honor jobs for the family, or tap friends to help you.Surely somebody in a big Greek family knows how to cut a cake. See if Mom and Dad saved the cake cutter from their wedding and use it, or buy them a new silver one. Check to see if they saved their toasting glasses, if not, new glasses with silver design!
Cute idea: buy/make a tiny cute little silver ribbons to decorate the glass bases with, and buy/make a gold one just like it, and wrap it up, with a cute note about how successful the first 25 years were, and how everyone is looking forward to the next 25.You could bribe your Dad to give it to your Mom, or make it from all the guests.
Enough ideas? LOL, have a wonderful time, and again omni is right, no surprise parties, give your Mom time to find just the right dress.
Answered By: riversconfluence - 9/15/2007