It could be just about anything that caused the problem starting with an improper shutdown that corrupted files to a bad installation of an update of almost any kind. It could also be malware.
Because it could be malware, after your system is functioning normally (hopefully now), update your anti-virus program and run a deep scan.
I would also recommend running a couple of web based av scans using Internet Explorer, as the web based scans require Axtive X to function.
Here are a few web based av and anti-malware scans:Web based online Antivirus and anti-malware scans:
(these can be run regardless of whatever else you are using. You must use Internet Explorer to run these as they require ActiveX to function.)
Kaspersky Anti-Virus Web Scannerhttp://www.kaspersky.com/service?chapter=161739400#betatest
File scanner and virus scannerhttp://www.kaspersky.com/scanforvirus
Panda Activescan http://www.pandasoftware.com/activescan/co...n_principal.htmhttp://www.pandasoftware.com/products/activescan.htm
Trend Micro antivirus and malware scan:http://housecall-beta.trendmicro.com/en/st...orp.asp?id=scan
Etrust Anti-virus web scannerhttp://www3.ca.com/securityadvisor/virusinfo/scan.aspx
Avast Online scanhttp://onlinescan.avast.com/
F Secure online scanhttp://support.f-secure.com/ols/start.html
Trojan scans –
Windows Security Trojanscanhttp://windowsecurity.com/trojanscan
See instructions for it here:http://www.windowsecurity.com/trojanscan/trojanscan.asp
To make a system state backup you use the Windows backup utility and be signed in as an administrator.
The following is from Windows XP Pro Help:
The Backup Utility Wizard starts by default, unless it is disabled.
Click the Advanced Mode button in the Backup Utility Wizard.
Click the Backup tab, then in Click to select the check box for any drive, folder, or file that you want to back up, select the System State check box. This will back up the System State data along with any other data you have selected for the current backup operation.
You should always keep current, reliable backup copies of your System State data.
You must be an administrator or a backup operator to back up files and folders.
To start Backup, click Start, point to Programs, point to Accessories, point to System Tools, and then click Backup.
If the Backup and Recovery Wizard does not start by default, you can still use it to back up the System State data by clicking Backup Wizard on the Tools menu.
Store the backup on your slave hard drive - not the one Windows XP is on, or, make two copies, one on each drive. The reason for that is if the hard drive your op system is on fails you will still have the backup on the second drive. You seem to have only a 10gb master, so maybe the backup on the 40gb slave drive would be sufficient.
Subsequent sets of backups should be set to be incremental - to add or change only what has changed, or you can do complete backups and then delete the previous ones. They will take a lot of space so you can easily fill a hard drive with many copies of full backups.
Anytime you need more information on this you can just open Windows Help (start>help) and type in what you are looking for - in this case it would be System State Backup.