My baby sister was living with me for a while and I knew she was online all the time, so to "spy" although that's not the way I'd put it, I went to www.logmein.com and downloaded their program so when I was at work I could log on the my home computer and when she would used it. I could see everything she was doing as if I was sitting next to her. To my surprise, she was giving out my address and phone number to meet men. This program only works if you can access another computer as far as something to record and then play back the past actions to you, I have no idea about that. Hope this helps. =)
There are several programs that can record every keystroke hit and every website visited. And allow someone access remotely into your computer. Some of these programs can be installed at the root level of your computer and are hard to find if you are not a computer geek (and I use that term in a good way). If you think someone may have loaded such a program onto your pc, call a geek. Or take your pc into a pc repair shop and they can find it. Regular spyware programs won't necessarily find something if it has been installed at the root level.
I really am not a computer geek, and often ask others to help me with mine. Sorry honey.
Most of the isp programs already have an in installed program to watch over internet use. AOL is especially good at this. If you do install a "watch" program, you will have to set up passwords so another user cannot re-configure or by-pass..
One similar type of program is Timbuktu. There are others.