Yup for $250 new all you can really get is a Huffy, and it will be destroyed.

For $250 used, you're looking at a hardtail with midgrade components, probably OK for a starter bike. Just make sure it fits you, and try to take it out if you can and make sure you feel confident about balancing on it.

For value, your best bet is Giant, nobody really offers a comparable bike package for a better price. The other option is to try to find some 06's that are being cleared out, but I think the time for that has passed.

Edit: Well, if you're just looking to go on dirt roads, there are some cruiser types (check out Giant) that will do the trick for around $250.