Aaarghh laptop grinding to a halt

[Missymoomum]

I've got an 18 month old laptop running Vista that has suddenly started going really slowly. I've not downloaded anything to introduce a virus but i've done a full virus scan just in case, i've done a disc cleanup and removed a load of photos on to the external hardrive which has meant i've now got well over 110 gb of 250gb of hard drive space free, i've de-fragged as well and it's still going slowly. The only thing i've installed recently was some Sony photo software that came with a new camera but i've just uninstalled that too to no avail.

Does anyone have any tips or suggestions please?

Thanks in advance

Ooh good idea, thank you. I hadn't thought of that! I will try in the morning.

Thanks for replying so quickly!

Sorry i didn't relpy sooner. I tried it but it didn't work!

I think it might be something internet related as it only seems to go slowly when i'm on the internet. I think i'm going see if my DH can get someone from his works IT department to take a look at it. I'm worried there some weird kind of virus on it.