I thought Yoshimo's fate was clear. He submitted to a geas from Irenicus, and there is no earthly way to break it. If he disobeys an order, he will wither and die. To preserve what remains of his honor, he feels that his only choice is to die in battle (fighting you at Irenicus's command) and to pray that Ilmater (his god) will take his soul and spare him from an eternity in Hell for his sins.
As Yoshimo explains, "I can wither and die for failing to kill you, or I can fall in battle, and pray that my heart will find purchase with Ilmater. No redemptions, no second chances! Let us get this over with! I stride into the hell that Irenicus promised! Ilmater take my heart, I have no choice!"
That's a clue for you to take his heart to a temple of Ilmater. If you do, your party receives 200,000 experience points. That's all you can do for Yoshimo. Irenicus's geas is too powerful for you to break (perhaps a god could do so, but a mortal is unlikely to receive such aid), and Yoshimo's fate in the afterlife rests with Ilmater (the Crying God), who will determine whether he deserves relief from the torment that his shame has brought down upon him.
The game designers went to a lot of trouble to make sure that you cannot get around Yoshimo's fate. Just get used to it and accept the fact that his time is up.
Look on the bright side--you can restart. Some people enjoy doing that frequently.
As for your PC troubles, I can recommend a few ways to protect your computer from viruses, trojans, etc. in the future. First of all, there are two easy ways to prevent your web browser from going to malicious sites that could upload "malware" to your computer. 1) You can use a customized HOSTS file that will deliberately misdirect your browser to the wrong IP address if your browser tries to go to a site on the list. A good HOSTS file that is ready to use can be found at
http://www.someonewhocares.org/HOSTS. 2) You can add malicious websites to the Restricted Zone in Internet Explorer, which will restrict the actions they can perform. I use IE-SpyAd, which is a simple utility that will add thousands of websites to the Restricted Zone.
I also run AdAware manually on a regular basis, and I have Norton Antivirus running in the background at all times. (I use an older version that works perfectly well with Windows 2000.)
If you have a broadband connection to the internet such as cable internet, DSL, etc., then you should use a broadband router with a built-in firewall. I like D-Link and Linksys products.
I can't remember the last time I got a virus on my own computer, but I've helped other people remove viruses from their computers. If an antivirus program can't do it automatically, it can be done manually, but you have to know what to look for. Normally, the malicious files can be found in the root directory, the Windows directory, or a temporary directory. You can usually find them by looking at the programs which your computer runs automatically when you turn it on. If you boot up in Safe Mode, they won't be running, and you can safely delete them if you can find them. There are some really bad ones that run as "services" as well as some that can disable your antivirus scanner, but again, Safe Mode will prevent them from running. The worst ones are the ones that infect your hard drive itself--they can only be removed if you wipe your entire drive. I don't think using a Restoration Partition will help you in that case.
