I think iPlayer is clearly for computer experts and not an every day user like me
It's not that bad, the volume goes up to 11!
I've had problems with it too, I find it plays better streaming than when I download programmes, which I found a bit odd.
Suggestions? Are you leaving other tabs open when watching a programme? Or to expand on what Zion Ravescene said;
Try hitting the CTRL, ALT and DELETE keys at the same time. It won't restart your PC like it did in days gone by, instead you'll be presented with a screen that calls itself the Windows Task Manager.
Click on the "Processes" tab on this screen, you'll be shown all the programmes, little and large, that your PC is running and how much memory they're using.
Background Windows processes on my own tend to use a few thousand k of memory, programmes I've installed to run in the background like anti-virus suites use a few tens of thousands of k of memory and something big like Firefox can use up to a hundred and fifty thousand.
If anything on the list you don't recognise is using a lot of memory (maybe as much as Firefox), you can shut it down or Google the name of the process to see if its harmful and if it can be removed.
A piece of malware got on my PC a while back and slowed it down so badly it couldn't manage to run a DVD without it skipping and jerking all over the place. I did the above, found something I didn't recognise and got rid of it, DVDs played just fine afterwards.
Of course, there's no substitute for a fast machine and fast net connection
