There is no general best investment valid for everybody. People with high risk tolerance have different favourite investments compared to let's say retirees. I personally don't think that bonds will do well in the next several years, but I might be wrong.
Mutual funds are not at all good for short term investments (like you are planning for only 2 years). I would go for some other funds except mutual fund.
Right now it is best to wait the markets to cool down - every day we have such swings - it is unbelievable. If you keep your cash maybe this will be your best investment