Got my in-laws laptop to try and fix, its running very slow and would not send / receive emails.

Managed to get it up and running, takes 2 hours after being turned on to become responsive. Did a scan with bullguard and came out with nothing, spybot search and destroy has found quite a few registry errors and some PUP's but nothing major.

I uninstalled a lot of useless programs, such as dvd writing software, photoshop basic programs etc.

When the laptop is booted into safe mode with networking, it goes onto firefox no problem, can view and download as normal, but will not work when in normal mode. IE8 will not connect at all. Sends and receives emails as normal now.

Any clues as to the problem? Running XP with SP3. Oh, and the system restore is not working, does its thing then comes on saying 'windows cannot restore to this configuration' with every date I tried.