Windows XP loads malformed

Okay, so windows was (is) playing up as usuall, I was viewing an email in outlook express, tried to open the attachment and mozilla froze on the startup splash.

All pretty normal considering that my anti virus (Avast!) stops outlook from connecting to the server when it's running (Don't know why this has been happening lately). So I stop Avast and try again, while the mozilla splash is still there. It all goes to pot and I have to do a hard reboot.

On startup (now) windows takes ages, like 5 mins to get past the "windows is starting" screen after the boot loader etc and after it has loaded the takebar has been hidden (like the edge was dragged too low) and when I try to drag the line back up it won't hold the click. Various commands won't work from command line (no services have started) and when I try to run the restore (from the windows/system32/restore folder, it says (when in safe mode as it won't even load in normal mode) that I should restart windows and try again as my computer isn't protected by restore (the hard drive IS being monitored though) The icons still appear in notmal mode.

I don't run a firewall but my router has a packet firewall (I don't know the difference tbh)

Can windows xp really go this bad after just a hard restart?

Hmm, sounds like a virus to me.

You disabled your AV protection, opened an email attachment, and now you can't run commands on the PC. I would suggest you immediatly do an online virus scan from Trend Micro or Symantec.

Only one problem with that: windows needs various services to connect to the net. I tried to start various services (mainly web client) with the services tool in the admin section of the controll panel but it wasn't working at all.

The attachment came from the RMA department of creative labs so I doubt that it was the source of an infection.

Is there anyway to change the default services that start using regedit or some other programme (one that coult be burned to disk and booted outside of windows)?