Norton Internet Security or Norton 360?

Does Norton Internet Security do anything that Norton 360 does not do?

 

My Norton Internet Security 2010 will be up for renewal in a while, but I already have two un-used licenses available for Norton 360, which I purchased for my 2005 Dell P4 Desktop running XP, so I am wondering whether, instead of renewing NIS, I should just use one of the unused licenses for N360 I have already paid for.

 

Maximum protection is important to me, because my Acer Aspire 7720-6395 laptop running Vista Ultimate is already having problems:  after turning on the computer, and using it for a while (the time varies) I lose control of the file and web browsers, all of them.  When I lose control, the browser automatically goes to the top of whatever page I am on, and when I scroll down, the page goes right back to the top.  I think this must be the result of malware that is either infecting, or did infect the computer. 

 

Some time ago, NIS showed that I had an MBR virus, and this occured at about the same time as my browser scrolling problems started, but NIS no longer shows the MBR virus...  In any case, I am looking for the most aggressive protection possible, in the hopes of getting rid of this problem, and preventing new ones. 

 

Thanks for any help that anyone can provide.