The lower the Debt to Asset Ratio, the better, as companies with high amounts of debt introduce more risk. You certainly want to look very hard at companies that have more Total Liabilities than Total Assets, as this is a precarious position for a company to be in.
Depending on the industry of the company, you might expect the company to have two or three times as many assets as liabilities. Anything less than this might be a signal that the company is running into trouble.