If you haven't already, you should read this thread, Newbie to guns? Need help? Where to start?
This is full of good info and will help a lot with new shooters. Any gun from a reputable company will probably serve you well. To me, the most important thing when looking at a first gun is how it feels in your hands. If I can't hold the gun comfortably, I wouldn't buy it. Try a few out, see what you like best, and make your decision. Also, it is a good idea, if possible, to rent some guns from a range to actually fire some rounds. Good luck to you, and be safe.

For that money, you better go with a used Ruger or S&W revolver, or maybe a Glock or Ruger semi-auto, if you're lucky. A new $400 gun is going to have a few drawbacks. The SW9VE started life as the Sigma, and had a few problems. Supposedly they have been ironed out, all except for the horrible trigger, that most gunsmiths won't touch. Then there is the Taurus, which many swear by, but just as many curse.

I would much prefer to save up about $600, and buy a known performer.

Thanks for the replies guys. I wouldn't mind buying a used gun at all. Ill be going to my local gun shop this saturday to have a look around. Ill keep you guys (and gals) updated on what I find.

The S&W you mention is a reliable and accurate handgun that doesn't cost a lot, but it's trigger is known to have a harder pull than most other standard-sized polymer handguns. Given it's price, I don't feel it to be out of line, and I've read that the trigger will smooth out over time. As long as you realize that it's trigger doesn't match that of higher-priced guns, then it will serve well as a range or home defense gun.

That being said, I would also say that most anyone would be better served by spending a bit more and getting a Glock or XD (not technically a DA only) or M&P. A better trigger might help your accuracy, and it's easier to find accessories for these much more popular pistols. These will certainly be more fun to shoot. Glocks and M&P's can often be found new for right around $500.

If you just have to stay under $400, then you might also look at the Taurus 24/7 which can be found new for around $350. Although this isn't a true DA-only, it nonetheless makes a good range gun. If however you want a defense gun, then you might want to look elsewhere. My 24/7 is a very good range/fun gun that has been 100% in function, but I won't depend on a Taurus as of yet for defense purposes.

Lastly, the Steyr MA1 used to be available in your price range, so you might look around for that one. It has a very good reputation....