Perhaps this could be a good time to buy gold and sell stocks. However, it is not clear if the current price of gold (less than US$300/troy oz A.D. 2000) is due to cyclical demand changes bottoming out the market or if this is a more long-term adjustment. Also it seems from historical trends that investing in gold is not a good strategy unless an investor is desperate to hold value, rather than to try and gain value. Gold is a commodity; it does not earn money in of itself because the invested money does no work. It can only "earn" money if the price of everything else falls relative to gold.
I have read about a new process for the extraction of gold dust from very low-grade ore, such as the tailings from older operations. This process is of such efficiency that the price of gold fell by around 1/6, from US$384.17/troy oz in A.D. 1995 to an average of US$331.02 in 1997. The further decline in the price of gold was due to national governments deciding that gold was no longer a good asset to hold. In particular the Bank of England has sold off large amounts of gold resulting in a further decline to US$278.88/troy oz in 1999. What does this mean? It means that there are quite a few signs that gold is not going to return to the same level of scarcity/demand that could produce a price of US$800/troy oz.
It is also possible that given the current capacity for the production of gold that even should cyclical demand rise (because of a recession) that the price of gold will not rise sharply. Unless inflation gets out of control again I doubt that gold will go above US$400 in the next 25 years. Because of this and the fact that gold is not a productive investment I think a better strategy is to invest in stocks and bonds for the long term.
Also note that the quoted price of US$800/troy oz was a one time high. The average for 1980 was US$612.56, so unless you picked the exact right day to sell it would not be easy to get that high a price.