Hello and welcome, datatron1, thanks for joining Android Forums!
Which phone to get is a difficult question to answer, as it comes down to personal preference. I see the devices you have mentioned above, all of which would make a great first Android device - I would always recommend getting as much Android as you can afford... the high end devices (such as those you mention) offer a different experience to the lower end devices. I know this, having compared my Desire HD with my mother in law's budget Android phone!
I would advise going to a phone shop and getting a bit of hands on time... you might like the feel of one phone in your hand more than another!!
I understand what you mean, when you say you don't want to get a device and for it to be outdated within a couple of months, but I am sure I've seen that the newer devices are being guaranteed to be updated for (at least) 18 months... if a contract is 2 years, that means that the phone would be updated for most of it's life. If you really worry about that though, you would probably be best with one of the Nexus devices... these are Google's own (manufactured by various brands)... I understand that the Nexus S (which was released in 2010) has just had the JellyBean update (which is the most recent version of Android).
If possible, it is worth getting an unbranded device, rather than a network branded one... the unbranded ones will usually get updates direct from the manufacturer and will not have a load of carrier bloatware on them (although, I am not sure if the Nexus phones come with carrier bloat).
Hope this info is useful... let us know if you have any specific questions - hope you find this place useful