I'm not a financial adviser so can't officially give you advice but I would give the banks a wide berth if I were you, especially if you're a novice investor as they will only recommend their own products which you may be too inexperienced to realise are not good buys.
If you are earning and are a taxpayer, I would certainly take advantage of your annual Cash ISA allowance of �3,000. for 2007/8, and perhaps put another �3,000 in each of the following following two tax years. Kent Reliance Building Society does not pay the highest interest rate but is a consistently reliable performer if you don't want to be chopping and changing and moving your money every year to get a better rate. Meanwhile, if you've invested �3,000 in a Cash ISA this tax year, I'd browse MoneyExpert.com which is is an excellent financial website for recommending high paying savings accounts in which you could invest the �7,000 remaining after buying your first cash ISA. If you want to invest some of your money for the longer term (where it will eventually hopefully grow faster than a cash savings account), go to the Hargeaves Lansdown financial website (h-l.co.uk) where their Research section will give you details of numerous funds in which you can invest for a stocks & shares ISA which is also tax free. But if the stockmarket frightens you, you might be better opting for an internet based high interest savings account like ICESAVE which I believe is currently paying 5.9% interest and guaranteed to be above the Base Rate until 2009. And I'd forget any large investment in Premium Bonds. They offer a very poor rate of return.