Wifi is one of the simplest livable networking solutions ever. It has its problems, i.e. security issues, but for 90% of us it works great.
From the time I plugged in the Access Point and made my Sharp Zaurus SL-5500 PDA talk to its Linksys WCF12 it has been great. No wires ,no errors and a livable speed.
Later I picked up a used Compaq Armada 7800 and a cheap PCMCIA Airlink+ 802.11b wireless NIC. It was generic, using the Prism2 chipset. So it isn't perfect either but I have the laptop dual booting Windows 2000 Pro and Redhat Linux 9. The Linux install actually went easier than the the win2000, no drivers to load, the prism2 is supported out of the box. Now I am doing all my work on the web site from my living room.
It comes down to Speed and Money.
A. Is a faster, 54 Mbps, and operates a 5 Ghz. It therefore has less problems with other 2.4 Ghz. devices, such as cordless phones. The main problem is the cost, 802.11a cards and access points are usually at least 50% more than 802.11b. The range is ~20 ft. also.B. Is the oldest standards in use and at 11 Mbps. might seem slow but before the 100 Mb. NICs became available, everyone lived at 10 Mbps. for years. Remember that your Cable Modem runs at 1~1.5 Mbps. and most DSLs are 256 kb, therefore 11 Mbps. is plenty fast. 802.11b cards can be found for just about all computers and PDAs. Most wireless Cafes use 802.11b. There are many APS/Routers that work well Linksys made my router and it has been solid for years. It has a range of ~30 ft. There are versions of the hardware that will support a "turbo", 22 Mbps mode. This requires the same make Access point and NIC as it is a proprietary standard.
G. Is the newest standard and is something of "the best of both worlds". It back supports 802.11b but in G to G mode runs at 54 Mbps at 2.4 Ghz. A few manufacturers are offering 3-way wireless hub/access points that support A/B and G. If you are taking your PDA/laptop out to a wireless cafe the G will serve you well as it still supports B but you can have the higher speed at home. US Robotics has come out with a "turbo" mode G but it only works with their own NICs.Once you have the basic hardware, install and placement become the prime concern.
The main worry about placement, of the AP/router is "Will I get a good signal in the places I want to use my laptop/PDA." The signal from an AP/router is a large sphere, and the signal strength/speed drops the farther you get from the device. So you need to place the AP/router high and centralized to cover all floors and rooms.
As signal strength drops the protocol reduces the speed of transfer, so the network still works but slower. don't expect the fastest speed available at all times. Weather conditions, such as storms will also effect the signal.
Every network manufacturer makes good gear and bad gear. I have seen them all. Don't expect things to be perfect, you will be disappointed. Work with it, if it is so hard to use it becomes more trouble than it is worth, take it back, try a different brand. Sometimes the off-brand/generic works as well or better than the branded. If you stay behind the curve, a year or two, you will usually get better results.
As of now B is an old solid technology, it works, there are hundreds of products out for it. If you want fewer problems just stay with B.