Seating Cards for E-Party...how do I address people?

I need advice on how to word the seating cards for a few different instances.

For husbands and wives should it be:
Mr. & Mrs. John Doe
OR
Mr. & Mrs. J. Doe

For friends with a date should it be:
Mr. John Doe & Jane
OR
John Doe & Jane Smith

For single relatives/friends should it be:
Mrs. Jane Doe
OR
Jane Doe
OR
Mrs. J. Doe

And I feel funny giving our grandmas a seating card like:
Mrs. Jane Doe
is it innappropriate to do:
Grandma Doe

Thanks for your help!

PS: These aren't really my family and friends names but I'm sure you already knew that

Has everyone gone to sleep????

It really depends on how formal your e-party is going to be. If it's very upscale then I'd say go more formal (Mr. & Mrs. full names) but if it's casual then you can do something informal (no title, just names).

I didn't have an e-party but for my wedding I did:
Mr. & Mrs. John Doe for married couples
Mr. John Doe & Ms. Jane Smith for friends with dates
Ms. Jane Doe for single friends

Whatever you decide should be the same for all guests, meaning if you use their initials or full names or whatnot. It shouldn't depend on their current 'status.

As for my grandparents I called them Mr. & Mrs. but if it makes you feel more comfortable to use Grandma Doe then go for it!!

for my eparty, by my personal choice, i did everything totally casual and fun. my grandfather's first name is Joseph but he has gone by his middle name is ENTIRE life so I put Ron O'Hara (not even Ronald or Mr. Ronald) just b/c I wanted it to be fun and easy-going.

So for FH's cousin: Chris DeGaetano and Guest
My friend: Jason Diament and Guest
My FIL's: Vinny & Fran Rella

It was nice this way So for an e-party, IMO, it's toally up to you!