Toilets?

So I think we might need to get one or maybe two new toilets. The ones we have are too low; also, what is up with push-button flush?
Looking for opinions on one or two piece; brands; round or elongated?

elongated.

I just had four different ones installed in a two houses we're renovating. Here's what you need to know: (note - I'm in the US, I don't know how what's available elsewhere)

• Pushbutton on top means it uses a pressure-assisted flush rather than just the usual gravity. You open the tank lid and see a big black plastic thing instead of water. These theoretically flush better, but make lots of noise and are more expensive. IME, not worth the cost or the noise.
• There are several heights available, measured from the top of the bowl (not including seat) to the floor. 14-1/2" height is "standard", i.e. low. Over half sold are now "comfort height" or some other name depending on brand, 16-1/4" to 17"h. Finally there are some extra-tall commodes about 18"h mainly for handicapped/wheelchair accessible use, sometimes called ADA height (Americans with Disabilities Act). For my 5'8" frame, 16-1/2" comfort height is about perfect. Shorter adults or bathrooms frequently used by kids may be better off with the low height. Elongated bowls are required by building code in some areas, especially in condos.
• One-piece toilets lack the gap between the tank and bowl, which looks neater, eliminates a seam that gets soiled and hard to clean, and makes the toilet easier to install since you don't have to put two pieces together. But they cost more, since they must be shipped in a large box instead of two small ones for the tank and bowl.
• Round bowls are the small ones. Elongated bowls are the same width but about 2" longer. That makes it more comfortable to sit on for everyone, but really makes things easier and more sanitary for men (please don't make me explain why; use your imagination). Elongated bowls usually take up a bit more room and may be a tight fit in small rooms; however, there are some "compact elongated" toilets that manage to fit the larger elongated bowl in the same space as a typical round-bowl toilet by using an extra-thin tank.
• Toilets in the US (and many other countries) are no longer allowed to use much water. 1.6 gallons (6 litres) per flush is the max, and many use only 1.28gpf. Some use even less, required in some places in California. This is down from 3.5gpf allowed in the '80s, and often 5gpf before there were any water-conservation standards. In general, 1.6gpf units flush a bit better, though there are exceptions. Also, 1.28gpf toilets have a rather small area normally covered with water, which can sometimes be problematic.
• Finally, verify the distance from the mounting bolts (usually under caps near the floor) to the back wall. 12" or thereabouts is most common, called a "12 inch rough-in". But you may need a 10" or 14" rough-in to fit your house.

The seat is often not included. Spend the small premium for a "soft-close" seat whose seat and lid won't slam down. For parents of preschoolers, there are triple seats available with built-in child potty seats that fold up for grown-ups.

There you go, more than you ever wanted to know about toilets.

Awesome. Thanks guys! We (in US) currently have two elongated, one-piece, 1.6 gal, low toilets, they are both American Standard but slightly different models. I am 5'7", and having spent a significant time sitting recently :( I think that the two we have are too low.
I'll measure the rough-in but expect that it is a standard distance.

I have just found the Terry Love plumbing forum, they seem to talk up the Toto Drakes quite a bit.

So we should expect to spend around $400 each then (not including seat)?

You should be able to get a good one for under $300, i.e. these:

http://www.homedepot.com/p/Gerber-Viper-2-Piece-High-Efficiency-Compact-Elongated-Toilet-in-White-GHE21519/204413109#specifications
http://www.amazon.com/CST744SG-01-2-Piece-Toilet-Elongated-Sanagloss/dp/B0012HBQK8/ref=sr_1_1
http://www.amazon.com/CST454CEFG-01-2-Piece-Toilet-Elongated-Sanagloss/dp/B002CQ4NVM/ref=sr_1_4

let's try that first link again:

http://www.homedepot.com/p/Gerber-Viper-2-Piece-High-Efficiency-Compact-Elongated-Toilet-in-White-GHE21519/204413109

I could read this kind of real toilet talk all day

one suggestion i have is start every conversation about toilets if you are in a store (or any plumbing really) with "i am not flipping a house", generally this will cut out 50% of their recommendations.

Dang. Noted!