Wireless router works one way and not another

[#1]

I am having problems with a wirelss router 'Netgear DG834G'.  My wifes laptop can print to my computer, the lan messenger 'Real pop' works fine, but we can't see each others computers and she can't access the internet.  It seems very complicated.  I have just secured it to WAP2 and thats when the problems came about.  On the laptop it did ask for the security password, which I put in and that hasn't worked obviously.  Why can't they make things simple and easier, ah that would be too simple wouldn't it!  Before I had put the security on it was fine, I only put it on as a just in case. Well, we live in West Wales and the nearest neighbour is half a mile away, but you could just have a roma going around with a laptop trying to get some small pickings.
So How do I repair it or how can I get rid of the WAP2?  Thats the question(s).
Looking forward to your reply
Tony

[#2]

Have you accidentally turned on Wireless Isolation?

[#3]

Hi Tony,
Have you tried doing a factory reset and reconfiguring your settings?

[#4]

Thanks for your ideas.  'Reset' I presume is on the back of the router?  And as for the 'wirless isolation', not sue about that.  I am on XP and unfortunately my wife is on Vista.  Vista I haven't gotten a handle on, but o'boy it ***** me off.  It keeps asking me if I wish to 'allow' things to be done!  Thats another matter.
Tony

[#5]

There should be a pin sized hole on the back of the router.  If you hold that down for 10-15 seconds, it should reset all of your settings, allowing you to reconfigure your settings from scratch.

[#6]

Well the router is not the problem.  The problem then is the WAP settings etc that have been set and I am not sure what the process is there to deal with it.  Any help?
Tony

[#7]

not sure what your problem is but if its just that the vista lappy cant connect to router now u changed to wap. when i messed around with my sercuirty wen i first got my dg834g. if u changed the passpharse r changed from wep to wap. i had to go in to network and sharing centre. then mange wireless conections and delete the saved connection with the old passpharse or wep setting the go back to connect to and type in the pass pharse then wen its connected the do u want to save this connection option should come up say yes and the lappy will connect auto to router.   
thats the only thing i could think of from what i read bout your probalem. hope it helps in some way

[#8]

Thanks for your help.  Did resolve it, but as you say you have to go deep into the properties and this was one digit out on the DNS. 
Tony