I have found a free software download which is particularly useful. It is called "Mozilla Firefox, Portable Edition". I am sure many people are familiar with the Mozilla Firefox browser. The portable edition is simply just that. You install it on your memory stick and have a browser with all your favourite sites, passwords, etc which you can carry around with you. Very handy if you travel a lot, go on holiday or just visiting freinds.
Here is the link.
http://portableapps.com/apps/internet/firefox_portable
It takes up about 30Mb of memory.

Another nice free bit of software is a screensaver from Magnetic. There are lots of free wallpapers (some incredible photos by the way) and screensavers. One I particularly like displays your personal photos by throwing a handful of them on the desktop.
The link is..
http://www.magentic.com/splash/t/conf_dl/dl_1.aspx

I have been using these for some time now and had no problems with the software, popups, spam, etc.
Enjoy
Don