wireless channel choice

[#1]

My wireless connection is set on Channel 1...... looking at inSSIDer, ... I can see it has 2 others on same channel....  ch 1 covers 1,2& 3  My sig level is 30 .... other two are 70 and 80 respectively
the next group of 5 stations is centered on chan 6 , so covers 4,5,6,7 & 8  these have much lower sig levels ( max is 80)
the next group of 3 stations centred on channel 11 ( all sky boxes) . covering 9,10,11,12 & 13 ( highest available channel) ( sig rating max of 60) 
So, would I be better off changing to channel 6 , or opting for an overlap on either 5 or 7

those on channel 6 seem to be giving the lowest signal level, ( if I were to try and connect, I suspect they would report out of range, they are so low)... 

[#2]

From those figures I would suggest you try channel 6.
It is always best not to overlap channels. As when two networks are on the same channel and in range they can co-operate. Where as overlapping can cause issues without the benefits of co-operation.
If possible switch to the 5GHz `a` band. As there is much less interference. And as the signal does not travel so far fewer other networks.

[#3]

Thanks for the reply..... will go to chan 6.....  I don`t think the Tecnicolour 582n has 5Ghz...... at least, no signals are being shown on inSSIDer on 5Ghz... ! so assume it is not available.

[#4]

Is it advisable to manually select a wireless channel other than 1, 6 or 11?

I set my router up to use channel 13, and AFAIK this hasn't been problem, but would this be detrimental compared to 1, 6 or 11?

[#5]

Only if you have Dell products My printer will not use channels 12 and 13.

I use channel 13 and have not noticed any (other) problems.

Phil