How can I make Linksys more reliable

I'm an IT person at a hotel, with several different buildings. As demand arose in recent years, I introduced and expanded wireless Internet access. I currently have some 10 Linksys Wifi access points and/or routers.

Guests come and go and they bring different makes of laptops (including Apple Mac-s) and I do a lot of configuration help out for them.

One thing that doesn't want to go away is this: every once in a while these Linksys Wireless devices need reset. They simply disappear from the wireless network, and I can't even ping them from the wired end. Sometimes they are still visible in the list of "avalibale wireless networks" from a computer, but while the bars show full signal strength (which I think is a bogus data at that point), the computers can't connect to them. I just have to get up from my desk, go over to the other building, pull the power plug, put it back in, and we are back in business. BUT WHY????? Why do I have to do this?

Sometimes they run for days, some for even weeks, sometimes the same device have to be reset every day for a period of 2 weeks or so (whenever a particular guest wants to use it, it crashes every day. Then the guest leaves, and it's back to normal: reset once every 1-2 weeks...)

On all of them, I use the basic security feature of 128bit WEP encryption. For a while I also used MAC filtering or switched over to WPA security, but these didn't make any difference.

So basically, any general suggestions as to what makes these things run more reliably? I have WRT54G, WRT54GXv2, WAP11, etc.

Or should I just start over from scratch and do it with another brand?

One more data: In one building, the deiveces don't overlap in coverage, but in another building, they do. In this case, I still have the same SSID, but on not overlapping channels, so guest computers can find the one with the stronger signal and associate with that one.

Also, when I list up the available wireless networks, there are other ones from surrounding buildings, so in some cases I see 3-4-6 available networks, and that may also be a reason for all these. But then again, maybe not...

All suggestions are welcome.