Could anybody let me know if they have experienced a problem like this?

I connect to the internet using an Mtel Huawei Dongle, very often my PC hangs on shutdown and after a period of 15 to 20 minutes I get the Blue screen of death. I checked the hex codes and these correspond to a driver error

The second problem, which I believe is related , is that often after start up and when connected to the internet, something kicks in, in the background and uses up all my system resources. This happens to the extent that sometimes a complete system lock up occurs, mouse, keyboard, graphics and even a short press of the power button does not initiate shutdown. Sometimes this clears after a few minutes sometimes not at all which leaves no option but a hard shutdown (absolutely not a good thing to do but there is no other choice). I tracked this down to svchost.exe using task manager (13 counts of this were running!) I checked the most RAM greedy of them and found out wudfsvc (Windows driver foundation). The total amount of RAM for all svchost functions can on occasion exceed 800Mb. To the internet again and checked on svchost.exe and apparently this can be quite hungry but 800Mb seems a little too much.

I disabled automatic updates for a while but the dreaded wudfsvc still functioned

The problems started after starting to use the dongle, the first time I connected the message appeared that my AVG subscription had expired, I dutifully paid for an extension and downloaded the latest version. This caused a problem with the identity protection using up all the spare CPU cycles, a little research later and to my delight discovered that he only viable solution is to disable this via services, that being done the problem of the spare cycles being used disappeared.

I suspected a driver conflict, so uninstalled and reinstalled the dongle software from safe mode but to no avail.

System Details;

Vista SP2 (old but so am I)
2 Gb RAM
AMD Athlon 64 X2 Dual Core 5000+ 2.6 GHz
250 Gb HDD
32 bit
Windows updates are all current

So, I think there are 3 possibilities

1, AVG software
2, Huawei dongle
3, Mtel software

Somebody please help me with a little advice on this because at the moment I can only see 2 options which are dump the AVG or find a provider that either doesn't use a Huawei dongle. The first I've paid for and would be reluctant to do the second is a contract service which I would have to continue paying for until February

Did you un-install all previous software that you may have been using for access?

Hi, [You must be registered and logged in to see this link.],

Firstly thanks for your reply, there was no other software used for internet access but I'm getting to the stage now where I'm starting to consider a complete rollback to factory conditions. This has it's drawbacks, AVG ca.350Mb, Upgrades for AGV, ca. 150Mb plus windows upgrades after SP2. At an average of 7Kb/s you can understand how this is not my primary choice, with an interruption to the service all downloads are dumped and with a "fragile" connection such as mine the initial download for AVG alone (uninterrupted) took 3 days

Sorry can't help you with this one but good luck.