I have turned off the automatic updates for windows as a few weeks back it messed my computer up!
I am using Firefox as a browser and want to install Windows virus updates only, how do I do this without having Explorer as my browser?

What do you mean by Windows Virus updates? Are you using Microsoft Security Essentials? If so, it updates automatically. If not, you can manually download and install Windows Updates from one of two sites. Other than that you need to use IE as Windows Update requires an ActiveX control which only runs under IE.

I used to use this site for Windows Updates when I wanted to do a manual download and install, works with any browser: Windows service packs & updates for Windows 7, Windows Vista, Server 2008 and Windows XP

You can also get updates from an MS site but it takes more work: Store Windows Updates locally for subsequent installations

Thanks for the link, yes I want to install the updates manually, as the guy who repaired my computer after it crashed through the automatic updates told me just to install the virus ones that i need rather than all updates?

Sorry but i don't know of any virus updates other than for MSE as I mentioned. You can look at each one and see what it says but most are going to be fairly generic. Look at the partial list for 2010:
XP_2010_Updates.jpg

They are all security updates to close one hole or another that allows an attacker access to your computer. Is that what you mean when you say virus update?

Rather than trying to select what updates to apply, it might be better to first get a good backup of your current, working system using software like Macrium Reflect (free) or Acronis True Image ($$$). I use Acronis and backup to a 2nd internal hard drive every night, an internet based backup site (Acronis) every night just for my data and an external hard drive every month or two.

Once you have a good backup then start applying MS Updates in groups of 10 or so till you find the one that is causing problems, reject it then set Automatic Updates to notify you but not install in the future.