Broadband Plus v Broadband Your Way

[#1]

Thanks, the download speeds apear to be back to normal now, although I still get temporary hanging or freezing of my screen on opening web pages? Is there anything I can do to stop or minimise this?
Can I ask why on my connection it says the speed is 6.7MB, but my IP profile is set to 5.5MB and I never achieve speeds above that?

[#2]

Have a look at this page (particularly the table titled "Full list of available IP & bRAS profiles used by BT Wholesale on IPStream maxdsl products" about half way down).
If you sync between 6240kbps and 6784 kbps BT will assign you a profile of 5500. 
You'd need to sync above 6784kbps to get a higher profile.

[#3]

It is also worth mentioning that the IP Profile reflects the idealised useful download capability of the connection when transmission overheads (ATM and TCP/IP) are allowed for. Those overheads total about 13%; 6528kbps sync speed less 13% comes to 5679kbps, which BTw round down to the IP Profile of 5500kbps.
Actual download speed is less than the idealised value due to real data transmission effects, such as establishing the connection, acknowledging receipt of data packets, requesting and waiting for retransmission of missed packets or those containing an uncorrectable error, ….