Erasing Partitioned Flash Drive

Earlier today I decided to use a flash drive and load the Lion Recovery Assistant on there - anyway changed my mind and now I want to use my flash drive as just a flash drive. It seems though that recovery has partitioned my flash drive and I can now only access 700mb of it.

I went into disk utility and tried to erase and re-format the whole thing, and had the error Partition failed with error: could not open the device or something like that. I can erase the 700mb part but not the other. I've tried multiple times with multiple formats, and on a Windows PC and nothing has worked.

Does anyone know how I can erase and format the whole drive?

I am not at a Mac right now so might get the terminology wrong, but in Disk Utility, I am sure there is a function to remove all partitions then repartition as a single partition. Right now, you probably have two partitions on the drive.

If you can get that far, it's just a case of formatting the new single partition as you require.