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For the 1 buffet do the Bellagio.
Other recs: La Creperie at Paris for sweet or savory crepes
Chinois at the Forum Shops for Asian fusion
B & B Ristorante at the Venetian for Italian
Aureole at Mandalay Bay for American and the wine
Shintaro at Bellagio for Japanese

I second Mon Ami Gabi. Excellent food and charming view of the Bellagio's dancing waters from the patio.

Red Square in Mandalay Bay is a wonderful Russian place with walk in vodka freezer. The food is good and it has a fun atmosphere.

And yes, if you must do a buffet, the Bellagio's is good.

This won't fall under the "nicer" meal. For the experience, pretty decent food, great drinks (they look fun - I don't drink, but everyone I was with loved their drinks), and excellent service, check out Quark's Bar (har har), the Star Trek themed restaurant at the Hilton. It's fairly inexpensive too. I know it's geeky, but it was a lot of fun. Granted, I was at a SOE fan faire with 600 other geeks.

Cassaendra: Is Quark's Bar still open? - or did it go when the Star Trek Experience closed in September, 2008?
Bethae : How long will you be in Las Vegas? Will you have a car? Are you the adventurous type? There are so many great locally owned restaurants all over town...
Yes, the Bellagio buffet is good, but so is the buffet at the Rio. Most of the big hotels do a good job, and going for Sunday brunch is best. The cheap all-you-can-eat buffets of olden times have mostly gone away.

Grand Lux Cafe inside of Venetian is great. It's pretty much Cheesecake's twin, but if you don't have a CCF in your town like me, it's a real treat.

Social House in Treasure Island is a wonderful sushi place.

In-N-Out is right off of Las Vegas Blvd and costs about 6 bucks by taxi. It's just a west coast thing, so again if you're like me, you'd enjoy trying a place you can't eat at everyday.

Bellagio has wonderful little snack places like gelato and crepes.

As for drinking-- there are about 10 bars for every party style out there!

WOW have a great time!! I wish I was in Vegas right now...

Ooohhh ... I just remembered! For a real Vegas-y experience ...
The Four Queens Hotel in downtown Las Vegas has a restaurant called Hugo's Cellar. (It's not too far by cab.) The food and service are wonderful. The menu includes tableside Caesar salad, steaks, chops, duck ... well, American cuisine.
They also have a fairly extensive wine list. The concierge at your hotel can make reservations for you.
As long as you are downtown, stay for the Fremont Street Experience. There is a huge canopy over what used to be Fremont Street. At intervals, the canopy lights up, and gives a great show! Vegas-y and cheesy all in one, and it's free. This will also give you the opportunity to shop for Las Vegas mementos as there are many souvenir shops and kiosks right there.
I have lived in Las Vegas most of my life, and that is where I have taken visiting friends for a night out. No complaints yet!

Thanks for the information. It looks like I will arrive late morning on 4/27 and will leave on 5/1. My coworker has been to Vegas before -- but I don't know her foodie-ness. I have to inquire but I didn't want the first things I said to her about the trip to be "where should we eat?"

I will hit the Bellagio for the buffet. The rest are still up in the air. I would love to get over to In and Out burger so I can say I tried it.

What do you guys think of Simon's?