I'd say to invest it in improving your own home, as it will increase its value and you don't get taxed when you sell your principal residence (as one MP knew very well.) I'd still advise even with the credit crunch. If your home has lost twenty K of value, and things don't improve, then it's never going to go up again anyway. If however you do it up then the price will go up thanks to the improvements and you won't get taxed. Winner, surely?
It depends on your financial circumstances. Generally if you have any debt, you should pay that off as a priority. The interest rate being charged will be much higher than you can earn in any savings account. If you are debt-free, you have to decide what level of risk you're willing to take. Low risk investments would be an ISA (which is tax free) and can be invested in cash, or stocks or a combination. Higher risk might be to buy some shares. It very much depends on your personal situation and the amount of your inheritance. If its a lot, it would be worth spending some of it for an Independent Financial Advisor for profession assistance. Hope this help!