What is the best mutual fund for long term hold

Unfortunately, there is no easy answer to this question. Forbes
publishes mutual fund reviews annually and Morningstar dedicates
considerable resources to tracking and rating funds. Both Forbes and
Morningstar would be good places to start. They have online info on
funds.

As to what would be best going forward, it is really unknowable. But,
given two funds with similar performance, the one with lower costs
would provide greater total returns to the investor. Vanguard
specializes in cheap, index funds that mirror the performance of the
overall stock market.

Another approach is to buy an exchange traded fund (ETF), like the SPY
(which tracks the S&P 500 index) or Standard and Poors Depository
Receipts. These are purchased like a share of stock, have low costs
like Vanguard funds and have little tax ramifications until they are
actually sold.

Anything that tracks a broad, diversified group of stocks and has low
costs, like the aforementioned Vanguard funds or ETFs, would be a good
make sense.

sp500 index funds

http://www.fool.com/mutualfunds/indexfunds/indexfunds01.htm

Make sure the fund you pick is NO LOAD. No Load mean no commission.
Which means that if you invest 10,000 - 10,000 is invested.  It also
means that if you WITHDRAW 10,000 you get 10,000 (this type is called
a back load mutual fund)
 
I could go into the long reason why index funds are best, but I won't.
 The simple reason they are the best is first, the expenses are very
low and secondly, very few mutual funds out perform the sp500.

I hope this helps.

I recently did research to decide where I'll be holding my IRA
account.  I decided on Vanguard.  Their fees are much lower than
anyone else I could find, and their investment strategies and returns
are also above the standard.

The average Vanguard fund has only a .25% expense ratio (meaning that
every year you will be charge $2.50 for every $1,000 invested). 
Typical mutual funds average over 1% expense ratio.  Also many
Vanguard funds have no load and no other fees.  The 1 fee that you
will likely be charged is $10/year per fund you're invested in until
you have $2,500 in that fund at which time the $10 fee will be waived.

Here is a list of their funds (including index funds):

http://flagship4.vanguard.com/VGApp/hnw/FundsByName

I recomend a lifetime fund to start (ie "Target Retirement 2045" or
"Target Retirement 2035" depending on when you're planning on
retiring).  They have a nice blend of an index fund and other
reasonable investments that are selected on the basis of how long you
will hold the investment.  The expense ratio is only .21% or .22% for
these funds.

And I also highly recomend that you invest in this fund using an IRA. 
The IRA will give you a nice tax break and will cost you nothing
(except that you cannot remove the money until you are older without a
10% penalty).  Currently you can put up to $4,000 per year in an IRA.

Best of luck to you in your investing endeavours!  Please write back
with any questions.  I (and I'm sure many others here) would love to
help in any way we can.

You really don't want to invest all your money in just one fund. You
want to diversify a bit. At the very least you should hold both stocks
and bonds:

     http://www.efficientmarket.ca/article/Stocks-Or-Bonds

and in the stock equity portion of your portfolio you want to hold
assets in many different asset classes. You want a lot of exposure to
the US market, but you also want to diversify out into Europe, Asia,
and so forth. That way you are not adversely affected if one of those
economies tanks. (Sometimes they all tank, there is risk that cannot
be avoided).

As for mutual funds themselves:

     http://www.efficientmarket.ca/article/ETF_Investing

The above is written for Canadian investors but the advice works
generally. The main difference is that in the US open-ended funds are
cheaper than ETFs. You should look into the Vanguard group. What you
want is to select an array of funds in different asset classes with
the lowest fees possible.