70 Euros. I'm not sure how to go about finding out if the computer's full.I've a Mac with Windows XP on it.......
Ah, there's your problem.
First question: why? Second question: how? Dual Boot where you pick which one when you boot up or Virtual (OS inside an OS)?
To find out what's going on, open up with Mac OS. Go to Apps/utilities/activity monitor.
This will show you as a chart how much memory you have and what's being used by running apps. It'll also tell you generally the memory size and how much is used by files.
If it's close to maxing out, then you need to clear some stuff out.
If you've loads of video and photos stored, then these are the easiest to clear out and back up on an external drive. It doesn't have to be wireless, it can be USB and there's much larger ones available too.
But you can just drag and drop them into the external drive and delete them from your hard drive.
Photos don't take up that much room, and in fairness neither does music unless you've a huge library.
Videos will though, so if you loads of videos, that could be the problem.