I went from analogue boards and 2-inch tape and later ADATs, to Digital Hard Disk Mackie stuff, to Cubase (for about 4 years) and now I'm on to Pro Tools. I will work on any DAW, but after doing some records with Pro Tools, I definitely prefer it. That being said. I agree with METALTASTIC... Learn on a small, inexpensive unit. No sense in jumping in head-first when it's easier to test the water slowly.
BTW... Pro Tools is the easiest DAW I've ever learned to use. And LE is not that bad. Yeah, it's only 32 tracks until you buy the Production Bundle, which you should get anyway, so you'll have Sound Replacer and the other plugins that come with it. And the Plugin Latency is NOT that big of an issue. There are not that many RTAS plugins that use but so many samples. And you can compensate the latency, if you need to, on the fader in the mix window. As far as external plugins, you can go with the UA stuff that has automatic compensation built in to the PCI card. And I'm sorry, but if you need to run a shitload of external plugins that use THAT MANY samples, you probably shouldn't be working off of a low to mid level DAW like LE or Cubase or Reaper anyway. If you're packing that much heat in plugins/tracks/etc... You should be using HD.