Hides browsing but not password protected sites

Since I've been inundated with Spam, I thought I'd try this program. I don't surf porn sites which I know are notorious for spyware and other things. Just through my daily surfing at major Web sites like aol, cnn, amazon, etc. I've somehow got on mailing lists. I have very mixed results with this software. First it seems to hide my address when browsing normally. However if I want do go anywhere which requires a sign in, even if it is free, then the program interferes with the Web site loading. I'm not very technical so the to the best of my knowledge, I guess it can't handle online certificates. I guess anything with a sign in is more secure so even if you are signing in just to read a news article the software doesn't work. Perhaps there are people that use anonymous surfing programs for nefarious reasons. However most people would just like to surf without someone following their movements or jumping on the opportunity to spam them. Anonymizer has limited success so it may be good to some extent, but doesn't handle a lot of web sites.