Be VERY VERY afraid to mess with your registry

Someone recently had problem with an error message. A frequent poster on this site suggested, among other things, going into the registry and making changes in order to keep the message from appearinig at startup every time. The person who had the problem replied that the fix (I suppose the registry fiddling) worked. As it happened, I was getting the same error message. I had read several times in the past that no one except a computer technician should EVER touch the registry, but I thought, if it worked for so-and-so it must be OK. I followed the instructions with meticulous care because of the warnings I remembered reading (and hearing). What a disaster! The error message is gone, but so is Internet Explorer, and my scanner won't work anymore. I spent about 10 hours between 8 PM and now, 10:30 AM, reinstalling Windows XP twice, going through my XP books, calling my internet provider, calling my anti-spam provider, and talking with a man in India for about an hour and a half. Miraculously, after painstaking detailed diagnostic work and reconfiguring, he was able to get me on Mozilla and the new Google browsers, so I at least have internet access again, but he was not able to get Internet Explorer back up. I am so glad to be back on the Internet I would use any browser that works, but I am used to IE and somehow, someday want to pay someone to fix things back like they were. I'm sure that the advice given on Computer Talk is given in good faith, but please be aware that if you don't know what you're doing, you are taking a risk, and it can cause a mountain of grief and frustration. I am so tired I have to fall on the bed and get some sleep, but I hope this makes enough sense that you will NOT make changes to your registry just because you read something in a magazine, online, or elsewhere. It's too dangerous.
The only other advice I took from Computer Talk had to do with my keyboard not responding at times and my having to restart the computer. I asked about it, and got a reply telling me that if I disabled something or another in Preferences that was a sure fix. I am too exhausted to remember what it was. It appeared to work until my second or third reboot, and the problem was still there. It turned out the keyboard was simply defective.
I'll probably keep looking at these posts for jollies from time to time, but advice I'll get from professionals. No one should have to go through what I did, although I freely admit the fault is ultimately mine for messing around where I had no business being.