I have IE9 on my laptop and my desktop and I always get the slow-running script issue. You have to click it to make it go away so it's easy to fix but still annoying since you have to wait for it to appear after it's stopped responding - and I thought it was just my PC :-) I also get that security settings message and the IT guy who looks after me at home has been unable to fix that either so perhaps it's just a website problem. I agree that the website is generally easy to use for bookings etc and I usually use it rather than speak to agents by phone but these are also definitely two IT glitches I think.