Actualy, the Google Toolbar does not bring in add ware and will only be installed from the Google site. Same with the Yahoo bar. There are other adware bars though that either automaticly install or try to force you to install them.
I've never had a problem with the google toolbar. My guess is that there is something else wrong, but the google bar just happens to triger it, or it got corupted.
IE crashes all the time, for a number of reasons (though I can't remember the last time it crashed on my home machine, probably some time in 2003), and no mater what causes it, it's always the same error. My work machine used to crash all the time due to Java errors, but I'd get the same message. (Of course, I only had 4 different versions of Sun Java on it simultaniously, so who knows why it crashed

)
Speaking of which, if you have more than one version of Sun Java on your system, I highly recomend removing all but one of them. They tend to trip each other up. I have my computer setup to only use Sun Java if it's specificly called for, otherwise I use Microsoft Java, which tends to be a bit stabler, and works better on some sites.