BleepingComputer.com: I Can't Access Internet Properly

Hi there hope someone can help I have BT Broadband 8meg and everything was running fine until last saturday when i was online looking at something i got off the internet for about half an hour went back on but it kept saying page cannot be displayed i tried everything unplugged the home hub reset it but it will access the internet for about one minute it will run really slow and then suddenly it will say page cannot be displayed. I called bt they done all the checks and its running perfectly at 7meg so it can't be any cables or anything as i can actualy access the internet perfectly in safe mode but not in normal mode. i am using USB cable from home hub if that helps i cannot use ethernet cable as it was broken when delivered to my house. I hope someone can help as it is so frustrating. thanks in advance.

What browser do you use (Internet Explorer, Firefox, etc.)?
What is your Operating System (XP Home, XP Pro, etc., ....)?
Have you updated, and run your antivirus?
Have you done any online virus scans?
Have you run any Spyware/Malware programs?
What Spyware/Malware programs do you use?

I use windows XP, I have avg free anti virus and ad-aware 6.0 i am always updating and running tests and i use internet explorer. I forgot to say that i have had an engineer look at it at his place he cleared it of viruses and he got his internet working on it not straight away he had the same problem as me to start of with but when i got it home it still would'nt work but like i said it runs perfectly in safe mode so it can't be any connections. I hope it is something simple.