For word processing, I'm tempted to reinstall Windows to use Office. OpenOffice.org (OOo) is a huge pain in the ass to use.
In general, the app is increasing it's dependence on Java. What this means is that it's getting slower and slower as time goes on. Now you don't really notice with Writer or Impress but when you start crunching numbers or generating graphs with Calc, it slows to a crawl (sometimes it just crashes). In the process it's sucking out all my system's resources so I can't do anything else while it's dying.
Now down to specifics. Let's start with Writer. So when I type Ctrl+I, it means that everything after that should be italic. Does it do that? Nope. Sometimes it makes the word that you just typed italic. That's not what I want. So to get a word italic, you have to type it, select it and then press Ctrl+I. Same goes for bold, superscript, etc. Also the margins don't seem to have any consistency. I save a file (even in .odt format!) and open it on my roommates computer with Feisty on it, the formatting is all screwed up. The only way for me to effectively send it is via PDF, but then that gets rid of the editing process. *sigh*
Next comes Calc. Overall, this is the best one I've used (mind you I've only extensively used Writer and Calc but my experience with Impress was it crashed during a slideshow). I have two problems with Calc. One is very small, but annoying. When writing a formula and you use a function with more than one argument, remember that you have to use a semicolon (;) instead of a comma (,) or it will give you a #NAME? error. Of course, intuitively you assume that this means the function doesn't exist, so you end up trying to bypass it. This is really bad for a simple two-parameter function such as POWER(), especially if you have to have something in your formula like x^5. Once you get into something like e^x then you're screwed (unless of course you know that it's a semicolon). The second problem is the ease of making charts. Once you figure it all out, it's not really that hard and it mostly makes sense, but when you do it a different way, it's difficult to get back on track. For example, if you select the data you want to make the chart out of before you click the chart button, everything works fine and it's very easy. If you click the chart button before selecting anything though, it makes it a bit more difficult (it crashed for us).
Overall, the path of least resistance for OOo is like this: install Windows. Install Office. Do your work there.