Dead lawn mower happenings

So a couple weeks ago I told you about some problems (I created) with our lawn mower. Unfortunately, things have gotten worse.

Well, I guess it didn't have far to go from "potentially dead" to "dead", so it's not too surprising.

My father-in-law was able to get the mower running last week after I broke it, so I was hopeful that I might get another year or two out of it. That hope was killed quickly when I started the mower up yesterday morning.

I started the mower, and a ton of smoke poured out - that was expected. What wasn't expected was the really bad knocking. I decided to try it out anyway and made about half a trip around the house when it suddenly stopped with a "klunk".

"Okay, I hit something," I thought. Pushed it back to the garage (the starter is was still being a pain) and took the starter of to shim it better, and "Oh - that's not fixable." I saw a nice crack in the block.

It wasn't leaking oil very badly, so my Dad and I pushed it into the shed to deal with it later while I push-mowed the yard. Came back to drain the oil and found that most had already drained out of a supposed crack in the bottom of the block.

So, the mower is definitely shot (despite my Dad suggesting that I could get it welded - I think I've had it with this mower for now).

I'm looking for a replacement, but I'm not sure what type of replacement. I wasn't really sold on getting a riding mower to begin with since I'm used to push-mowing about a half-acre and can do our 1/3-acre lot in a little over an hour -- the riding mower wasn't a very big time saver. I'm considering a larger and self-powered push-mower; does anyone have any experience with the newer models and how well they do? The biggest reason we got the riding mower was to make mowing easier for Tiff to do, so it would have to accomplish that (ie, it wouldn't be able to make her keep up with it if it were a self-propelled). Thoughts?