Law of contracts
English law on contracts says some interesting things in relation to the process by which a consumer contract comes into being. This is especially awkward for the supplier for consumers rather than commercial purchasers.
The contract terms are those which the parties reasonably believed were the terms when the contract was formed.
The offer of variations on the contract after it has been formed may be rejected by the customer. The EULA is clearly such an offer and may be rejected. The contract with the supplier remains in force leaving an interesting situation. If you entered into a contract to by "Microsoft Office" then you have little come back except to reject the terms and ask for the contract to be cancelled (ie get your money back). If you went into a shop (PC World say) and asked to buy something for a specific purpose and the EULA is not suitable then the contract remains in force and they are required to provide something does meet your purpose. This is a whole new can of worms but the upshot is that the shop you buy from should be grateful if they get away with simply giving you your money back.
On the issue of software not working. It is required to be of merchantable quality and no amount of statements in the EULA saying they do not warrant it is suitable for a particular purpose will get them out of this. Basically it must be of "merchantable quality" for carrying out the tasks they advertise it for. If their advertisements talk it up then they are making some quality statements about their software. The EULA cannot negate this.
Unfortunately many of the nuances of the law in this area have simply never been tested in court mostly since if you apply legal pressure you will get your money back and that is the end of it. No industry wants their limited warranties tested in court since this might make consumers realise how invalid they are.
I have numerous warranty cards for bits of equipment that provide a "free one year warranty repair" for manufacturing defects. The law gives me a lifetime warranty against manufacturing defects.
From my point of view the key EULA restrictions that will stand up in court (probably) are the consequntial damages and licence transferability clauses.