I always leave updates turned on which is best but leave it set to notify you first before downloading so you can choose when its convenient so it wont slow down your PC when you are using it. I'm not a fan of Vista I prefer XP or Windows 7, and also,.. IE 8 is now the standard version,.. you could try Firefox, which is very good....
clicky and will import your faves etc and see if you get the same problems ?
Try wondows 7 as an o/s one of these days .. its very good

and you can get an easy a cheap u/g from a vista installation online from microsoft
here IE 8 will come free with it .. or a whole range of other browsers they are now obligated to offer you