The first currency converter I grabbed out of the air indicates that the 400 £ mentioned by Jon above is about $660 US, so the home-built 'nix machine is close to what I see advertised for packaged basic Windows machines.

"Student" laptops - which can cover a range from itty bitty urchins to possibly entry university level - start at around $360 (US) with slightly better equipped ones in "stock" configurations up to about $800.

If you can find a desktop, the price range for "basic packages" is similar to the laptop prices but the monitor is "extra."

You probably should think in terms of a "target price," for a "Windows package with some options" of around $600 - $800 for your use. (360 - 480 £?) It could run a little above that if you can pin down specific things you need to add, but that should get you into something quite usable.

If you want a Windows machine, it will require some "extra effort" to get anything other than Windows 7 now. The "ancient" WinXP still runs on about half of all computers in use, but is (always was) vulnerable to lots of "stuff that smells bad." Either Vista or Win7 are a whole lot more secure, and the last time I looked (3 or 4 months ago) a few makers still allowed you to opt back to Vista. Remember though, that the first ads for Win7 said "It's not Vista" as the selling point.

If you really want to do more than minimal multi-tasking, a multi-core processor is pretty much necessary, although lots of individual programs still haven't been updated to use multi-channel processing very effectively. Current builds nearly all use "quad core" processors.

In Vista or Win7, you probably will want a 64-bit OS version, which requires a machine capable of running it.

Vista machines were often sold with 1 GB RAM, and they'd limp with that, but 2 GB was generally considered the minimum for even limited multi-tasking. Vista 32-bit CANNOT USE all of 4 GB of RAM, but can use a little more than the 2 GB that's the normal next step lower. The actual "maximum" is somewhere around 3.6 GB. I'm not sure what the limit is for 64-bit Vista, but with your task description I'd say you really want at least 4 GB of physical RAM installed in any Windows machine that's viable now. 8 GB RAM would probably be a good option for Win7 if not a requirement.

You'll want a minium 500 GB Hard Drive for the OS, even if you add a second data HD. For what you indicate as your use, I would expect you to want a 1T HD for the data. I recently replaced a 500 GB HD, and found the replacement internal 500 GB priced at $87 and the 1T (same mfr) at $105, so the difference in price doesn't really justify cramping your style. The "markup" for an optional HD in a package may not reflect the small difference in retail price, but "it's a clue" to what's reasonable.

To do lots of "music" you probably want a step above the default "kiddie OS" that's the default in most packages. Microsoft has changed the versions available so often that I can't say what they call the current options, much less what to suggest.

Add-ons you'll probably (should probably?) want, will run the starting price for a minimal Windows machine package to around $800 or $1,000 (US) although that's just a guesstimate.

"Gamers" generally add graphics and RAM, and sometimes HD space, to drive what the sellers consider "game ready" units to $1,200 (for little kids) to $6,000 for "serious adolescents," but you probably don't need to get into that range.

While it's theoretically fairly easy to equip a laptop to the "same specs" as a desktop, my experience is that the laptop will do about 60% of what the "identical" laptop will when you get them in use. Raw performance isn't the only thing that matters though.

As a side note: HP has just announced they will cease producing computers, leaving only Dell as a locally recognized "main stream" manufacturer in the US. (No comment about support for those already sold.)

There are a couple of other brands at outlets here, but none with established reputations. Some news reports indicate that there are brands that have developed "name value" in UK markets, but most of them aren't sold enough here for us to hear much about which ones are any good, or how good.

If you're creating an "archive" of a lot of stuff, you need to think seriously about how you're going to archive-backup the archive, but that's a "separable" subject so best to wait - except to say "YOU REALLY BETTER DO IT."

John