NAV of a mutual fund depends on the duration for which the fund has been in existence and its performance. Rather than looking at the NAV one should look at the past performance to compare the funds.
Buying a mutual fund through a NFO only means that you are investing in a fund with no past performance. It is better to invest in a scheme with a known past performance record.
Not all mutual fund come with tax benefit. If you invest in a Equity Linked Saving Scheme (ELSS), your investment can be shown under 80(c). These mutual funds come with a three year lock-in. If your fund invest more than 60% of the corpus into equity and you hold the fund for more than a year, the return made on the investment is tax free. Income from other mutual funds are treated as regular income for the investor.
You need demat account when investing in stocks not for mutual fund. You can just need to fill up a application form, attach the check of the desired amount and submit the form at the mutual fund office or one of the customer service center.