The table itself shouldn't be to hard. Does it have any carving around the edge profile ? That could give ya a little trouble. How about the base. Is it a double pedastal style heavily carved ?

Do you need specific instructions ?
Strip using something like 5F5 or Zip Strip . Both have a jell like consistancy.
Apply liberally, and let the striper do the work for ya. Repeat the process a number of times. You might use a spackle knife to get the finish off.
Once it's relatively clean use steel wool and lacquer thinner to clean the surface.
Sand with 220 grit paper and get ready to stain.

The first thing to determine is if the top is solid wood or veneered.
Veneer must be treated very carefully since it is very thin.

Unless it's a crappy table from the late 70's to present with a MICRO veneer you're really not going to treat it any diffrently.
You're not sanding any more or less off if it's solid or veneer.
Yes you need to be careful not to spend to much time in one area for fear of burning thru, but if you maintain a "flat" sanding technique with your random orbital sander you should be fine.
To much time spent in one area on veneer or solid is not a good thing.

Don't be afraid of veneer, veneer is your friend .:)

It's solid. The table looks and feels like most of the finish has warn away. Also, I noticed that the table leaf is a lot lighter then the table. Which type of stain (oil, water or gel) would be best for staining the table? Thanks!

Most of the time, the table leaves were not the same wood as the table because they usually are covered by a tablecloth .Also most leaves did not have the apron that the table did. They were usually just a flat board.
Can you show us a picture of the table ? I would hate to see you stain the table if happens to be a nice cut of walnut.
Also tell me about the base/legs/pedastal.
The stain is not as important as the finish.

The table was a package deal that came with the boyfriend. Sounds like it was purchased around 1983, rectangle, contemporary-clean lines, with wide legs. No carvings. I'm at work so I can't measure it or take a pic but with the leaf it sits 8. If the table comes out nice and it's not too difficult, i'd like to change the legs.

"Most of the time, the table leaves were not the same wood as the table because they usually are covered by a tablecloth .Also most leaves did not have the apron that the table did. They were usually just a flat board."

Only in the lowest cost stuff.
Leaves are often a different color from light exposure of the table. It changes while the leaf is stored i the closet in the dark.

The most likely finish for medium price stuff from that period is toning lacquer, possibly catalyzed.
Catalyzed lacquer can be difficult to remove with anything except the most aggressive chemicals or by sanding.

Practice on the leaf first.

I'm sorry , my bad . I took "lighter" to mean not very heavy.
If it's a color diffrence it's probably because it was stored in a closet or under a bed and hasn't seen the lgiht of day in years.
Are you saying the table was bought new in the 80's ? I would doubt it's solid Walnut if that's the case. You might be dealing with a micro veneer.

take a pix and let us take a peek.

The leaf was stored in the closet so the color of the leaf was probably the color when purchased which is pretty light - closer to an oak. Now I'm wondering if it is walnut. I'll check it out when I get home. It is solid.

I put the leaf in the table so you can see the difference in color.

Here is a link that might be useful:

OK, now we've got some questions answered.
You're table is oak,not walnut.
It is solid, it would have been very unlikely that it was walnut and solid ( also would have been odd that it was so new and walnut).
My only concern is that you have to realize that trying to make oak look like walnut will be difficult. I'm not sure how handy you are,refinishing anything even a flat surface like this table is not as easy as it looks.
As far as stain selection goes, once you've stripped and sanded the entire table , use a leaf as your color sample and try diffrent stains on the leaf ( just a small section , make little "swatches" ). After you get the color you want, use some mineral spirits to clean off those stain samples , sand the leaf again and proceed with your staining.

Ok, now i feel really stupid. The rest of the house has a traditional-urban feel to it with cherrywood build-ins & cabinets, cherrywood & black furniture. I was thinking a darker color would match the rest of the house better. Any suggestions? I'm eventually planning on buying a formal set, maybe in a year or two.

First off, no need to feel stupid. You presented your problem and we got to the bottom of it.
If you are going to replace it sooner than later,I would not put any money into it . The set is not worth the thousands it would cost to have professionally refinished or the time and ( without question) the aggrevation it would cause you if you did it yourself.

i have a mid century modern dining set...i have a problem on hand..need to first establish the problem.. im have attached a set of pictures of the table top..except for the ring nd a few spots on one half, the other half is in perfect shape..

https://picasaweb.google.com/craigacs/TableTop?authkey=Gv1sRgCN3vucaF_u_cLA#

pl help...

Here is a link that might be useful: sudha sundareswaran