Connecting netbook - WEP, router and no of bits!!

Am on o2 broadband and have just bought an Acer netbook on XP that won't coneect (already have an Acer office laptop on Vista that connects with no problem). I am asked for my o2 WEP - which is 64 bits - and every time I enter it I get a message that says the "network password needs to be 40 bits or 104 bits". o2 tell me that my router only supports 64/128 bits and that they do not do one that supports 40/104 bits. Got 3 questions:
1. Can the netbook be configured to accept 64 bits?
2. If I change the router how do I find out how many "bits" a router supports (when I research routers this doesn't appear in any of the technical specification)?
3. What will happen when I try to use the netbook elsewhere - will it connect in wireless hotspots or will the 40/104 bits continue to cause problems with other networks?