I've been thinking of getting a laptop just for vehicle diagnostics for a while, so having missed out on a mate's stag weekend I've decided I can justify spending a few quid cos I aint spent it on a good time & a hangover! It's for use on my own, family & mate's stuff but at work I'm an agric engineer where we do get a few cars in to service, MOT prep etc so I can see it being of use there, my boss is a little reluctant to the benifits & need of such equipment so mabye it'll open his eyes a bit & he'll invest himself (or mabye I can earn a little from it!)
A little research suggests it matters little what actual brand so long as it has a spec capable of running whatever kit I choose & nothing very up to date is needed for most of them. So what should I go for in terms of reliability, standing up to being used in a workshop, being fixable & getting stuff like a battery or a screen hinge should something go wrong? More to the point are there any makes/models I should avoid!

I wasn't going to go daft with the spec but looking at getting something a bit better than the minimum required so it's well on top of the job & a decent amount of storage so I can put as many workshop manuals as I need on it etc, an extra £30-40 seems to get a fair bit higher spec. Seems to be plenty choice on ebay around £130-160.

Which operating system? I've heard many say Windows XP is best suited but is that true or is it just folk not liking change, having to learn a new system etc? Is there any danger of XP becoming obsolete to the point of not being supported (VCDS/VAGcom no longer works on windows 98 or earlier now according to their site)

How much does a serial port matter? We found at work the diagnostics for the quad bikes we deal in wouldn't work through a USB & heard the serial port was better for diagnostic work but the various diagnostic kit I've looked at uses a USB so have any such problems been overcome?

Any recommendations on what kit to go for? I like my VWs (own a T4 van, 52 reg Polo TDI & 2 mates run T4 vans) so VCDS is appealing but expensive for what I'll get from it & I'd want to work on other stuff too so I was looking at this following good reviews:
http://www.espautomotive.co.uk/catalog/scanalyst-award-winning-package-p-31.html

I'd like to a have a go at Megasquirt sometime too, anything that matters for that?

Thanks for any advice!

For in car use a 10.1" Netbook rather than a Laptop or Notebook is better because of the smaller size and much lower weight.
You can also use an Android smart phone or tablet with a suitable app to work with a blue tooth or wifi dongle although I don't know what is available with extra features for VW

However it is worth considering a hand held scanner instead there are quite a few on the market which combine OBD II with varying levels VW group specific features, from experience I can recommend either Autel or Memoscan brands. The Memoscan U600 or 585 would probably suit your need --- do an ebay search look for a seller based in the UK.

[Edited on 13/10/12 by britishtrident]

Thanks, I had thought about a proper hand held scanner & they're mabye better value but I'd still want a laptop for putting the manuals on etc so much of what I'm wanting advice on would still be useful if I do get a scanner. We use a laptop with the quads at work & I like the big screen, found a few faults using the live data displayed as a graph that would've been hard to spot otherwise. I do have a simple code reader which has proved very useful but it shows how much better I could do!
I like the idea of the smaller netbooks but there is far more choice/value with a full size laptop, looks like the less clumsy size would cost a bit more, mabye worth it though?

I havn't got & am unlikely to get a smart phone any time soon, don't like touchscreens & I'm happy enough with a simple robust phone for calls & texts, signal is'nt good enough to make use of the extra features for the internet etc. Ipod has my music, mobile is just a mobile & this will just be for working on cars etc.

Have a Autel scanner and a cheap Hp laptop (with seriel connector)

Use the Autel scanner for the code reading & live data and the laptop for running Easimap etc
Also have wiring diagrams and Autodata on the laptop

I'd recommend you keep an eye out for a laptop that still has a serial port, some leads still use serial ports (even the USB ones are still serial but they have a USB-serial convertor inline).

I go to www.bigpockets.co.uk for my laptops, this is what I use;

http://www.bigpockets.co.uk/product.php?title=HP-Compaq-NC6220-Laptop-Centrino-1.73Ghz-1Gb-40Gb-COMBO-WiFi-Win-XP-Pro&product=SOLV855

It comes with XP, but I can safely say it runs Windows 7 no problem, although you might want an extra stick of memory. 1Gb is only just enough. I'm fairly sure I paid less than a tenner for another 1Gb.

Well perksy's solution does have some appeal, decent scanner is cheaper than the kit to go with the laptop, can be had with Vag group extras & I can still get a setup to work on the laptop (which I'm pretty much certainly going to get for the CD manuals) at a later date. However I do like the idea of the Elmscan scanalyst as it's supposed to be user friendly & intuitive which for a beginner such as me has got to be a good thing, having all this diagnostic info is close to useless until it's interpreted correctly! And of course it has a calculated dyno facility which although nothing essential or mabye accurate could be fun!

And I forgot to mention, a mate & myself have been playing with a SAAB engined Astra using the t5 suite, all done with his laptop so far, so I'd be putting that on it too.

This seller on ebay has a few Dell laptops with serial ports:
http://stores.ebay.co.uk/essex-laptops/_i.html?_nkw=serial+port+laptop&submit=Search&_sid=75478126

[Edited on 13/10/12 by hillbillyracer]

Cheap netbooks are a good way to go.
Cheap to buy, cheap to fix (when you accidentally smash the screen).
Plenty of performance for these types of tasks, and lots of battery life.

If you need serial port then good quality adapters aren't too expensive (£20), cheap ones are less reliable but dirt cheap.

Any reason why this should be avoided?
http://www.ebay.co.uk/itm/DELL-LATITUDE-D520-1-66-Ghz-DUO-CORE-2GB-RAM-XP-160GB-HDD-SERIAL-PORT-/270973985168?pt=UK_Computing_Laptops_EH&hash=item 3f174ee190

It's not a fortune if I need to replace it,
processor speed & 2GB ram not as high as some but well above minimum specs I've found for diagnostic programs,
tons of space for manuals,
serial port if I need it,
fairly robust according to online reviews.
It's not exactly cutting edge, problem?

Still might go for a hand held scanner yet though!