Hi,well you can run hijack this and wait for our security team to get you a fix.
Or you can run a repair,not advisable if you have an infection.
You can back up all data such as pictures,files etc to DVD/CD,floppy or an external hard drive then reformat.A reformat is good for a PC/Laptop.
But remeber you will need to download the drivers for your laptop after a reformat.
Downloading and just running the driver downloads does not mean they automaticaly install,you need to go to device manager and install from there.Some driver files are downloaded and make a folder you can locate the folder and some of the drivers in there will have self extractors.
Then update to internet explorer 7,Windows media player 11.
Before you can install some updates you wll need to download WINDOWS INSTALLER 3.1 from Microsoft website.
I would let your son reformat as long as he knows what he is doing.
Once you have reformatted here is how to get your driver downloads.
Downloads - Support - Fujitsu Siemens Computers
Just type in box Amilo D7820 then choose notebook and operating system is XP or XP pro?
Save the link in your favs.
Make sure you check device manager and install the drivers,if you need help on any of these things please feel free to ask.
The RAM in your alaptop is fine,however when you got a few spare pounds I would upgrade to 1 gig RAM,Get son to check inside laptop to see if it has a spare RAM slot,if it does you could buy another 512 RAM,she would then fly after a reformat and updated drivers and a bit more RAM.
Buying more RAM is not a must only if you want to upgrade.