I think the best way to choose a date is to know the gal you're asking out. Here's some things to consider when coming up with some ideas (in my opinion):

1. What she's expressed interest in: Whether it's sort of a passing mention or something she's really passionate about. Try to look for something along those lines - and make sure that you're also up for it! Don't do something that's going to be a chore for you, because it not only sucks the fun out of it for you, but she might get the idea that she's boring as well. Do something that's common ground for the two of you.
2. Social energy demand: Has she mentioned being kind of introverted? Has she said something about loving going to busy, exciting places? Are you comfortable with the activity? Dates should be fun, and forcing her or yourself into a needlessly stressful environment isn't going to be a good time.
3. Physical energy demand: Don't push yourself or her to go do a thing like hiking a mountain if you're pretty sure it's just going to entirely drain both of you to the point where you can't enjoy each other's company. Don't be afraid to be adventurous if that's your thing, but don't go overkill.
4. Your Budgets: Whether you're splitting the tab, you're paying, or she's paying, make sure that it's something that's not going to burn a hole in both of your wallets. It's a lot easier to enjoy yourself on a date if you're not worrying about money.

Personally, I'm very low energy physically and socially and not really rolling in dough, so some of my favorite things to do are really just to hang out at a bar and talk. I also love going to arcades and things like that for a bit, then going on a walk and chatting about whatever - games, science, math, computers, movies, art, stuff happening in our lives, etc. Maybe we'd grab something to eat and then hang at their place for a while after.

There's a bar I know that actually has some consoles set up so you can play multiplayer games while you have a beer, and that sounds like the best kind of date to me!