Ok chaps, I am officially raising the white flag and asking for your help over this pc thing. I've been reading various sites and looking for recommendations but I'm not finding much of it useful as all they seem to do is tell you what to buy but don't tell you why, so when I can't find what they recommend for sale over here (mainly because the stuff they sell here seems to be mostly out of date

) I don't know what it's safe to choose as an alternative.
My requirements are fairly simple, I mainly want to watch tv (iPlayer etc.), surf, fiddle with pictures and animated gifs, SEDRE, play music, that sort of thing. I don't play any games.
The problem I had with my old machine is I had to close most programs down to watch tv as otherwise the frame rate went out of the window. Ideally I'd like a machine that would show tv on the telly while I can do whatever I want within reason using the monitor. Obviously I couldn't watch another channel or a movie but it would be nice to be on this forum while the wife's watching Midsommer Morons.
The telly we have presently is a Samsung LE26S8 which has HDMI & DVI inputs and the book says its happiest resolution is 1360x768
Ideally I'd like this pc to last for maybe 10 years (like the last one) so upgradability is the word.
The two main motherboard manufacturers here seem to be Asus and ASRock. Now as far as I can remember the original board in my pc was an Asus which only lasted about 18 months, while the ASRock I replaced it with lasted more than 8 years, so I think I'd like to go for them again.
I am also biassed towards Intel and nvidia, although I probably couldn't make a convincing argument as to why this is so.
I have a fairly new 620 watt psu and 20" TFT monitor.
I don't want an SSD as I'm a compulsive program fiddler. I'm not much worried about speed anyway.
The copy of Windows 7 at my wife's school (which I can legitimately use apparently) turns out to be 32 bit, I presume I'd be best off with 64 bit but it seems like an unnecessary expense having never paid for an o/s before

. Or I could use Linux 64 bit but then I'd have a hard job with stuff like SEDRE, so maybe I could dual boot for the time being.
Most motherboards seem to come with on board graphics these days, would this be good enough for the telly or should I think about getting a proper graphics card?
I have lots of SATA HDDs, I was thinking I could use two that I have now for storage, one older one for downloading and a brand new one for the o/s.
Now I found this board recommended
http://www.asrock.com/mb/Intel/Z77%20Pro4-M/ which I'd be happy about (I know myself and if I got a budget one I'd always be kicking myself for not spending a few more quid on a better one) but the cpu recommended with it (Intel i3-2100 3.1GHz) is unavailable here, so if I went up or down a processor would that affect the memory choice?
Obviously I don't want to spend thousands but, as I'll be paying for it on the never-never anyway, I can't see much point in buying the most absolute basic pc and spending the next 10 years regretting it.
What do you reckon guys?