I think the hardest part of choosing that first guitar is that you really don't have a frame of reference to compare against as you try different guitars. Certainly you will compare them each to the other, but the hard fact is that probably none of them will "feel" good to you since by gosh, ya can't play any of 'em! Plus, it can feel awkward to sit down and start trying out guitars when you can't really play. Some guy next to you may be casually playing some really advanced stuff and you're awkwardly holding a guitar and testing how it feels to play one note at a time. Don't let it stop ya. That guy was a complete beginner once too, and he probably remembers what it was like and would encourage you.
Having said that, budget is obviously a factor. If you are looking to buy an acoustic you could get an entry level Martin or Taylor or something along those lines for about $500 - maybe a little less. I've read very positive reviews for Taylor's Academy series that is really designed for beginners but supposedly still has great sound. I would expect something like that to be really playable and have great tone.
You can certainly get a very decent guitar for a lot less money than that, of course. I think the key for most of the inexpensive guitars is you really do want to spend the money to get a setup done by a good guitar tech or luthier. You might spend less than $200 (maybe as little as $100) on an acoustic and then spend an additional $75 to get it set up nicely, but that $75 is worth it. For a lot of beginners, including me, the temptation is to get a really cheap guitar because you aren't sure you'll really stick with it. I know my own acoustic is really cheap and initially it was really hard to play, although I didn't know it at first. I thought it was just because I sucked and didn't know how to play yet! But I realized how much extra work and pain I was enduring as soon as I got a decent setup. Even for a more expensive guitar, you may very well want to get a setup done, although often the base setup will be better than that cheap guitar.
Just explain that you are an absolute beginner and you need the action set as low as possible and you want some really lightweight strings. This will really make it a lot easier on the fingers. William MG got really radical with his acoustic when he started last year -- strung it with electric guitar strings, 9s I believe. He says he gets a bit of flack from some people who say things like you can't do that, it's wrong for the guitar and it's wimpy, etc. But you know what? It helped him train his fingers and continue to have fun learning instead of suffering and getting frustrated and giving up. You and me and William are in the same age demographic and I think we're old enough to not really give a damn what folks say.
One thing is for sure. If you don't like the way a guitar looks, you won't want to play it. So I wouldn't even consider trying out something that doesn't appeal to you visually. You have to feel good about the way it looks. That's true for an electric or for an acoustic.
I don't have as much to say about electrics if that's the way you want to go. There are plenty of decent starter sets that include a guitar, amp, cord, gig bag, and an assortment of picks for under $250 -- some for a lot LESS than that. One thing that experienced players have mentioned to me is that on some of those the amplifier is just really bad - enough to make you think something is wrong. I would rather buy separately and maybe spend $150/$200 on the guitar and another $100/$150 on a pretty good practice amp.
Just know this -- if you stick with this, your first guitar won't be your last. You'll want another one sooner rather than later. It happens to all of us! G.A.S. Guitar Acquisition Syndrome.
Anyway, welcome to the gang, good luck, and enjoy the journey!
Dave...
It takes as long as it takes unless you quit - then it takes forever and you will never get there.