Right. The simplified points I make above about chargers assume use for typical NiMH batteries (namely AAA'a & AA'a) which the OP was specifically asking about. AA & AAAs of both normal NiMH and Low Self Discharge NiMH type will be fine in any such charger. The one NiMH exception I can think of that is tangentially relevant around here is a special charger is required to properly charge higher voltage 9.6V NiMH rechargables (either normal or LSD) that some of us use in Nboxes and Church preamps instead of disposable alkaline 9V batts. But most users have seperate chargers for 9Vs verses AAs and AAAs anyway, and most manufacturers make seperate chargers for 9vs.
[edit- the complexity of using an advanced charger such as the Maha one Bean mentioned or the LaCrosse is mostly choosing between what mode you want (charge, dischage, cycle, break-in, and a few others that are combinations that I can never remember and have to get the manual out to remember what they do and what to use them for) and having to specify the charging rate you want based on the battery's capacity. Those options make the charger more universal and applicable to older NiCads and other things beside NiMH AAs, but a simple good-quality charger that you simply stick the AA's into and a LED for each battery turns green when each is charged is the best and most economical answer to Noah's needs IMO.