Good option if you will hold bitcoin for that long because you don't have to worry and spend that money you'll use to invest and as for altcoins, you just made a list of alts which can easily determine what coins you should buy. I'll eliminate the most and shall remain these altcoins that I think are good for me.
ETH
Litecoin
As long as he only chooses the top coins then at least it is the right choice for a long-term holding plan, he can spend his money without thinking or considering a quick return and that is already a good first step and all that needs to be done next is to remain consistent and if need to buy more and add a bigger portfolio, maybe it will be good in the future too.
There are top coins that I don't have on my list and neither want to invest because I simply don't like them. This should be the other investors mindset that if they are about to choose, the money that they'll allocate to that investment is good for nothing within a long time and doesn't have the obligations to be spent. It's all up to OP's choice, we've given significant suggestions and he's even more knowledgeable than the other investors that are asking what kind of coin that they should buy with lesser risk.