You know the newer PC will be much faster, but it also depends on your Internet speed for streaming video. A chain is only as strong as its weakest link, and you said nothing about your download speed.
I will be using this PC at home for surfing the web, sending emails, word processing and streaming TV programs and YouTube clips. I won't be doing anything too sophisticated, such as gaming. Also, I tend to do one task at a time as opposed to multitasking.
In this regard, I am considering two models. One is E-Value Code: D0066S50 (£279) and the other is E-Value Code: D0066S37 (£329).
For my purposes, as outlined above, would the PC costing £329 perform substantially better than the one costing £279?
At the moment I have a Dimension1100 (upgraded to 1.25GB RAM). With this, when I watch streamed TV, the picture can freeze or slow down. Would an Inspiron with 4GB RAM rectify this?

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