Two questions about messages
 

Hello. Running kde, my computer crashed earlier today for what appeared to be no reason. It was strange, i could use the mouse and open things by right click: i couldn't run a command though. I opened Dolphin through right click and navigated to /bin/bash, but it wouldn't open. I was able to shut down by right click, and selecting the leave option. is there a way i can find out why?

The second question is, about all them messages that speed past when you boot up; is there a way i can see these?

Can not say why your system crashed. I have just started to use KDE. Was gnome user till now. But you should be able to find links to both in /var/log/messages. If it was just the X that crashed, then x server logs should give you some idea.

You can check your /var/log/boot.log file
And also check /var/log/messages as already mentioned by chaitanya.

Type "dmesg" without quotes in the terminal or console of your choice. It's a lot of info so you might want to do it like "dmesg | less".