Hey - you're singing to the choir here.
To defend the indefensible a little though - part of the reason that all these old systems are in use is that we were told we mustn't spend on them as they'd be replaced by the National Programme for IT systems.
When that (predictably) didn't happen, there has been a semi-panic of trusts either buying new(er) systems (often properly configured version of the ones that failed during the whole NPfIT process) or starting work on updating the old ones. This often also means that the old PAS and clinical systems suppliers lost a lot of highly specialiased staff as NPfIT meant that a lot of them would be losing all their customers shortly, and the ones they had weren't spending anything with them.
But a PAS is a compex system and peoples live depend on it being right - and even where two Trusts run the same PAS, they will use it and have if configured very differently - so the updating, testing, configuring, re-testing process is slow.
Partly due to the budget cuts (more nurses fewer managers actually means fewer back room staff all round, and much less money for new PC's that will actually run anything later than XP) people are trying to do all this reconfiguration with too few staff, while at the same time trying to keep the old creaking systems running.
On top of all that, the government like to meddle, and the whole budgetary and reporting structure has changed 'to put GP's in control' and that mess has to be mopped up by the same people. It's not a good situation - but the people at the coal face are working hard to sort it out, despite what the press may say and what the general public think of this extended support deal.
This deal has not been made because we didn't want to upgrade to Windows7 - it's because we haven't been able to up to now.