Life on Mallorca is probably a little less convenient regarding access than where I live in the States, plus things are more expensive in Europe, so I can imagine why one might want to keep this system going instead of replacing it. This V6000 was apparently a very nice laptop three or four years ago. Reviews say models with the AMD processor were subject to overheating issues which would damage the motherboard. Sounds like you have something like this going on. None of those maintenance routines should take anywhere near that long. Vista is not the problem. I've had and have Vista on a couple of my notebooks and have no idea why Vista gets a bad rap.
I saw a fully featured Lenovo ThinkPad on Woot this morning for $199. It's already sold out but it's a good indicator of just how cheap really good system can be gotten these days.
As someone mentioned, wiping the disk and re-installing the OS is the best way to eliminate the bog (assuming you don't have a fried circuit in memory or on the MB, or a failing HD). You probably don't have the OS disks - but you may have the original OS in a small partition on your existing disk. Make some CD's from it and then you can wipe and re-install.
Here's a very useful and free program that will allow you to copy your disk to another disk - operating system and all, byte for byte. The copied drive is bootable and an exact duplicate of the one you've copied from. You'll need an external HD case with a USB cable and another hard drive as your destination disk. Once copied, replace the HD in your laptop with this new disk and see if you've still got a problem. This free program will do lots of other HD tasks as well.
MiniTool Partition Manager Software for Windows PC and Server
Mike
San Diego