The best advice I could give you about visiting the Hofbrauhaus is to eat before you get here. Don't just rely on getting food here, unless you like paying for a sampler of sausages that look more like Vienna wieners than sausages. Carb up at home or if you are in a pinch, stick with the Bavarian pretzel. You'll thank me tomorrow morning.
Hofbrahaus though isn't really so much about the food as it is where you take your friends when you want to be loud and drunk and it be acceptable. The steins of beers are massive. No matter what kind you get, those one liter steins are going to kick your ass. It's not a shock, I always have a hangover the day following a Hofbrahaus visit. Even if you tell yourself that you'll only have one (or two) steins, you'll get sucked into drinking more. That'll come either through a chugging contest or a spank shot. Who can resist taking a shot and getting spanked? No man I know.
I can't imagine coming here by myself, lest I want to stumble home drunk and hungry. Friends really do make come together. You want to share the experience of hearing a guy blow the Ricolla horn or singing the ziggy zaggy song. You're not getting that at Applebee's, no danke shun.
If you really want to experience this, come during the month of October. And better yet, bring a bunch of your friends. And even better better yet, bring a bunch of them in October and get them drunk and see what happens. That's the type of fun the Hofrbrahaus brings.