Computer D&D aids
For any computer aid, you have to sit down and think through what you really want to have your 'aid' do for you in your campaign. Do you want a program that does everything, i.e. you type, click, scan, etc EVERYTHING into the program and have it be the be-all-end-all gaming aid(with no need for any reference materials, notes, etc)? Do you want your 'aid' to do minimal things for you, just have tables, reference materials, etc for your campaign, so you don't have to lug books with you to the gaming sessions? Do you want something in between? Once you decide on which of the 3, then the advice you will receive in forums like these, will be much more helpful for you, because you can weed out the ones that don't fit your style.
The programs that allow you to do everything tend to be labor intensive on the front end(getting everything for your gaming session into the program) and have steep learning curves. BUT, once you get up on that curve, they do everything you could ever want during your sessions. Programs such as Roleplaying Master are good programs in this area.
The programs that are for minimal intrusion, which have tables, and reference materials all will do what you need, if this is what you choose.
My preference is for somewhere in between. I want my computer aid to do the things that take up all my time in a gaming session, without the program becoming the actual gaming session. Instead of having lots of bells and whistles which take away from the gaming atmosphere(IMHO) and remove the GM from the gaming session, I want my program to help manage and keep track of combat, which always bogs down in even moderate sized battles. I want the ability to quickly and easily reference any rule, monster, magic item, skill, Feat, etc right when I need it, without the dreaded....'He's opening up the books'. I want the aid to be able to keep campaign notes however detailed or sparse. I want the aid to keep all my NPCs and PCs in an easily accessible area. I don't need a program to make maps, dungeons, manage encounters (especially 3d mapping or 2d mapping movements). I want a program that manages the 10% of the things that DM's spend 90% of their gaming time on. For my money, you can't get any better than DMs Familiar! The program is excellent! The support is unbelievable. Todd, the programmer and designer, is always lurking on the messageboards, answering questions directly and is frequently coming out with updates and revisions to better the program ---- with direct input from the users of his program. Most of the SRD items are easily entered (via download) from another forum so you don't have to enter ANY of those things yourself. This program has a combat board that is second to none. You can manage combat in as detailed a manner as you want (except NO 3d or 2d mapping of the participants) or as minimal as you want (like I do.... keeps track of Initiative, turns, HP etc and let the players and the DM roll the dice). There is an easy 'codex tree' which allows you to enter your campaign notes in a tree fashion. Every rule, skill, feat, spell, magic or non-magic item is easily accessible and quickly searched for and found, in the programs databases with a simple click.
That is my LONG two-cents worth. Hope it help you. Thanks for 'listening.'