DIY
My ambition is to build myself a PC from scratch. Is this a realistic prospect for a relative layman? Are there any particular books, manuals or web resources that you would recommend? Finally, what operating system would you recommend? Leo Carroll

Jack Schofield replies: There are a lot of websites that explain how to build your own PC, and it is not difficult to assemble a machine from standard parts. The most useful sites include www.buildyourown.org.uk, Hardware Central and www.daileyint.com/build/buildtoc.htm.

A Google search will find many more. Consult Tom's Hardware Guide to find the best parts. Make sure all the parts you choose are on the Windows XP compatibility lists. Also, run a Google search on each part to find out if other users have experienced compatibility or installation problems (eg search for Asus+P4PE+problem). Conflicts are common.

I suggest you start with Windows XP, because Windows has the most software and hardware available, and works with almost all websites. However, if you partition the hard drive to start with (ie create drives C: and D:), there is no reason why you should not install GNU/Linux on the D: drive. If you plan to do this, you should also check parts for Linux compatibility, and avoid products such as Winmodems or "soft modems" and Winprinters. See: http://hardware.redhat.com/hcl/ and www.idir.net/~gromitkc/winmodem.html.

Upgrade now
My Windows 98 PC, from 1998, has a terminally ill motherboard, and must go. I am replacing it with a more up to date computer, but, as all my software dates from 1998 (Word 97, etc) should I install Windows 98SE so I can run all my applications satisfactorily? Simon Abbott

JS: If you were just swapping the motherboard then I'd suggested you left the rest alone. If you are buying a new PC then XP is the way to go - preferably XP Pro with 256MB of memory. XP Home and XP Pro are based on Windows NT/2000 code and no longer include the MS-DOS operating system, though they still offer a command line emulation. If you think you might have compatibility issues, check here: www.microsoft.com/windowsxp/pro/how tobuy/upgrading/compat.asp.

Everything, or almost everything, should work, because the shift from DOS to NT has been under way for a decade. Every software house should have noticed. If not, it is time to move on. You don't have to be on the leading edge, but nor should you fall too far behind.

Activate it
I have a new computer with Windows XP Home, and I am being asked to register my copy. Firstly, why should I have to register? It seems to me to intrude on my privacy. Secondly, what happens if I don't? Isabella Ramsay

JS: It is not registration, it is "product activation", and it is anonymous. It is included as an anti-piracy measure. You can also register Windows XP separately, and at that point you can provide an email address, if you want. However, registration is optional. If you do not go through the product activation routine, over the internet or by phone, then you will not be able to log in to Windows XP. You will therefore be unable to access your PC. See http://masl.to/?X20B12863.

Porn link
A site listed in the November 28 edition of Webwatch, which is supposed to lead to a cartoon/animation site, actually leads to a porn site. The address was www.toonzone.com but it leads to www.whitehouse.com. I wonder how many other hapless (and innocent!) males had to explain this away to an eyebrow-raising partner. Rod Bushell

JS: In this case you mistyped the address, which is www.toonzone.net - a mistake that can be avoided if you go to the online version of Webwatch and click the link. But porn companies often buy addresses close to popular sites to exploit this very common mistake. For example, www.whitehouse.com piggybacks off www.whitehouse.gov.

Nonetheless, you may well find that some old links do lead to porn sites. Lots of popular websites fail, and porn site purveyors buy up their old addresses.

Autokorekt
I used the "search & replace" facility when doing a Christmas round-robin. Now, whenever I write "Peter", Microsoft Word automatically substitutes "Dad". Penny Salkeld

JS: Go to Tools and select AutoCorrect. There you will find a Properties sheet with a list of all the corrections that Word will make. Select the one that you don't want and click the Delete button.

Backchat

· Last week, a parent was trying to protect his 12-year-old son from porn spam on AOL. Jocelyn Cole, from AOL UK, says he could set up mail controls to stop him from receiving emails from anyone other than designated friends and family. "For more information, members should go to AOL Keyword: Parental Controls or AOL Keyword: Mail Controls."

· Annette Ray asked about a spam email that told her to phone a certain number. This scam can generate profits if the number provides a kickback to the provider (eg 0871) or is a premium rate number beginning 090. Someone wrote in from a component supplier saying: "We recently received a phone bill for over £1,000 for over two days of calling an 090 number. We were not sure if someone had hacked into our network or this was caused by a virus of some sort. The dial out was done over our network through our server. Has this happened to anyone else?" Complaints about the abuse of premium rate services are handled by ICSTIS, which operates a compensation scheme.