After a more tame bike for family rides really and was thinking of a hybrid type thing…..

I can get a 58cm or 55 cm bike that looks to fit the budget (discounted)

6ft 1: inside leg 33

Hard to say, for example it depends on the length of the top tube of the bike in question. There are various "fit calculators" online that do a reasonable job of sizing you up for a frame e.g.

http://www.competitivecyclist.com/za/CCY?PAGE=FIT_CALCULATOR_INTRO&INTRO_LINK=NOREDIR&CLEAR_RESULTS=TRUE

I'm 6'2" with roughly the same inside leg as you and ride a 58cm roadie.

I'm 6'1" with a 33 inseam and ride a 58 Spesh Allez. and it feels perfect.

I'm 6ft with a 34" inside leg and again ride a 58cm road bike – Focus Cayo.

I am not sure the primary factor in road bike sizing is inside leg measurement tbh but if the bike is only for the odd pootle with the family I guess sizing doesn't really matter too much

I am 6ft 1" with a 34" inseam and ride a 19"/20" MTB and a 58cm road bike.

probably is the answer though obviously it depends to some extent on your proportions and the relative top tube length of that specific 58cm frame.

I am not sure the primary factor in road bike sizing is inside leg measurement tbh

this is true – there are so many things going on on a road bike geometry wise – and you tend to be sat in the same/similar position all the time compared with an mtb where you tend to move around a lot more, so fit is more important on a road bike.

However, top tube lengths are all fairly similar on a per size basis, though there are a few exceptions, so it's worth checking. Changing stem length on a road bike makes a good difference to bike fit and can be played around with very easily.

You will almost undoubtedly spend the first couple of weeks or month tweaking the set up slightly – seat height, bar height, bar angle, stem length, fore-aft seat position, bar-seat relative position etc…

i found though that with my long legs, short torso and long arms I need to go 58 to get the bar height (head tube length jumps considerably between 56 and 58 or medium-large in most ranges).

If it's your first road bike, it's worth spending a bit more and actually getting it from a shop where you can try lots unless you obviously fit into one of the size ranges offered by whatever manufacturer you're looking at.

what are you looking at, btw?

6ft2 and ride a 56cm trek 1.5, it,s their "comfort" geom rather than race though, so taller head tube for less of a flat back stretch as i like it for riding about rather than full on racing

bought one of these

in a 61cm as it felt right. That's the best way I suppose