Hi Claudia,
It sounds like you may have multiple problems with your computer…..
Here are some thoughts for your consideration:
1 it's unlikely that there is a "magic fix" that will quickly and simply make your computer 100% and running fast and sweet (at least one that we can apply at long range in the forum)
2 If I'm reading this correctly then the machine is only 4 months from a complete professional rebuild?
3 If 2 above is correct, maybe you could ask the repair firm to check things out for you free of charge….
4 Windows XP SP3 becomes an unsupported operating system in 14 months time (Microsoft will not be issuing any security updates or patches after that time, so the computer could become unsafe to use on the Internet after that time, so you may want to consider if it's cost effective in terms of time and money to get it up and running properly again when it has such a short lifetime ahead of it.
5 We don't know (at the moment) if it's a hardware problem or an operating system/software issue that is causing the current problem, so that might be a good first step to try and establish (There is no point in trying to fix problems by making alterations to Windows if in fact its the hardware that is the culprit.)
6 To help with step 5 here's a suggestion. Download a copy of Linux Puppy (available free) from here:
http://puppylinux.org/main/Overview%20and%…g%20Started.htm
7 Burn the .iso to a CD as an image…. ImBurn is good for this, (available free) from here:
http://www.imgburn.com/
8 Don't just copy the .iso to CD it must be done as an image… that way you end up with a bootable disc .
9 Boot from the disc, You may ned to enter BIOS and adjust boot priority order (CD/DVD as Priority one followed by Harddrive as two) if you do this then remember to save changes before exiting BIOS and your computer will then boot into Puppy…(press any key to boot from CD etc…)
10 Follow onscreen directions as to language, keyboard etc and ensure your Ethernet cable is plugged in to your ethernet port .
11 Puppy will run happily in RAM and will not write anything to your hard drive (unless you ask it to…… it does not even need your hard drive to be present in the computer….)
12 You will be able to use Puppy for all the normal things, (using the Internet, and if you wish opening photos etc) Give it a good try, its a bit different from Windows but you'll soon get the hang of it… (just remember its one click only to open stuff)
13 If Puppy works well then it has cleared most of your hardware as a potential culprit….. so we need to look to your hard drive itself and your Windows installation and software as the likely source of the issues.
14 You can, if you wish, use Puppy to copy any important files, music, documents, photos etc… that may have escaped being included in your latest back up (an external USB hard drive is ideal for this or a memory stick if its of sufficient capacity)
Post back and let us know how you get on….
Regards
paws