IE 7 Will Close Down If I Type In The Search Bar

I cannot pinpoint the exact date this first started happening, mainly because I use Firefox for most of my browsing. There are however some sites out there that still do not like Firefox.So on the rare occasion I am forced to use IE, I click on the icon IE opens, the second I try and type in the search bar it shuts down. I have tried upgrading to IE 8 and the same problem still exists.I have run my anti virus and also superANTIspyware, to make sure no nasties have made there way in. They both come up clean.Also if I get an email, that has a URL attached, I can click it open (IE is still mydefault browser), and it will take me to the page.But once again the second I try and type something into the search bar wham its gone. and if I try to use ctrl it disappears also.It never used to do this, I have to date tried :-

Upgrading to IE 8 (no difference)RED BACK TO 7
Reset all the defaults (no difference)
Been to this site How to fix Internet Explorer has encountered a problem and needs to close The first one works when i try regsvr32 wintrust.dll I get an error.The odule "wintrust.dll" was loaded but the call to DllRegisterServer failed with error code 0x80070005. do not know whether this is relevant or not, but I do not have MSN installed.

regsvr32 softpub.dll
regsvr32 wintrust.dll
regsvr32 initpki.dll
regsvr32 dssenh.dll
regsvr32 rsaenh.dll
regsvr32 gpkcsp.dll
regsvr32 sccbase.dll
regsvr32 slbcsp.dll
regsvr32 cryptdlg.dl1