Are there any inherent advantages or disadvantages of different investment classes (i.e. growth vs. value funds, large vs. small cap funds, bond funds, reits) when used in a Roth vs. a Trad. IRA. Also, are prefered stock funds apropriate in IRA's

The some factors that are more likely to dominate a choice will be your planning horizon, risk tolerance, investment experience/knowledge and how willing you are to spend time doing your own research. I would suppose that many Roths or regular IRAs are going to be held for the very long term (compared to saving for a house downpayment or college). Therefore, you can be less worried about the short term volitility of your investments, which favors growth stocks. Only a few investments are inappropriate (such as tax sheltered muni bonds), your investment style is more important.

One factor to remember, within any IRA, the holding time on your investments has not tax impact or even bookkeeping impact. Short term, long term have no distinction.