From the content of your post, it appears to be your browser that is crashing, rather than any problem with the actual internet connection.
If you're using Internet Explorer, you could try searching the Microsoft website for an update or a later version of the program. (Alternatively, try running System Restore and choosing a date prior to when the problem first started).
However, the vast majority of the 'regulars' here in AB's Technology section ditched Internet Explorer ages ago. Firefox is faster, more secure, more flexible and more stable. Download the program and use it instead of Internet Explorer:
http://www.mozilla.com/firefox/
Alternatively, quite a few people are now using Google's new browser, Chrome:
http://www.google.com/chrome
Chris