The answer is no. How? χ hide SSID -- yeah! router will not communicate or show anything to adversary, but sadly authentic clients tell adversary everything through the packet flying over the air. 5 min max-- to get that hidden name! χ MAC Filter -- similar to hiding SSID but sniffing client's MAC address is darned easy. MAC Spoofing also is easier. Router has no brain to check whether they are authentic or not. < few minutes -- to sniffing and spoofing χ WEP -- believe it or not! it can be cracked within an hour in normal-traffic network. No matter how large WEP is--64 or 128 bit is the same. Probably 10 more minutes. χ WPA/WPA2 -- it can be cracked too, but it's just harder. Dictionary attack can play the role quite well. Brute force attack is possible, but take time--a lot! √ WPA2 AES w/ long and complex passphrase -- although it can be cracked, it takes a long time to do so. One good thing with AES encryption is you will lose only a fraction of whole to header and security stuff.
I probably write about this in my spare time and will see how long it takes to crack thing. It's easier than you think.